Cost-effective,safe,and highly performing energy storage devices require rechargeable batteries,and among various options,aqueous zinc-ion batteries(ZIBs)have shown high promise in this regard.As a cathode material fo...Cost-effective,safe,and highly performing energy storage devices require rechargeable batteries,and among various options,aqueous zinc-ion batteries(ZIBs)have shown high promise in this regard.As a cathode material for the aqueous ZIBs,manganese dioxide(MnO_(2))has been found to be promising,but certain drawbacks of this cathode material are slow charge-transfer capability and poor cycling performance.Herein,a novel design of graphene quantum dots(GQDs)integrated with Zn-intercalated MnO_(2)nanosheets is put forward to construct a 3D nanoflower-like GQDs@ZnxMnO_(2)composite cathode for aqueous ZIBs.The synergistic coupling of GQDs modification with Zn intercalation provides abundant active sites and conductive medium to facilitate the ion/electron transmission,as well as ensure the GQDs@ZnxMnO_(2)composite cathode with enhanced charge-transfer capability and high electrochemical reversibility,which are elucidated by experiment results and in-situ Raman investigation.These impressive properties endow the GQDs@ZnxMnO_(2)composite cathode with superior aqueous Zn^(2+) storage capacity(~403.6 mAh·g^(−1)),excellent electrochemical kinetics,and good structural stability.For actual applications,the fabricated aqueous ZIBs can deliver a substantial energy density(226.8 W·h·kg^(−1)),a remarkable power density(650 W·kg^(−1)),and long-term cycle performance,further stimulating their potential application as efficient electrochemical storage devices for various energy-related fields.展开更多
A series of novel 1-methyl-3-（trifluoromethyl）-^1H-pyrazole-4-carboxamide derivatives were designed based on our previous work and synthesized. All these title compounds were confirmed by NMR and MS. The primarily n...A series of novel 1-methyl-3-（trifluoromethyl）-^1H-pyrazole-4-carboxamide derivatives were designed based on our previous work and synthesized. All these title compounds were confirmed by NMR and MS. The primarily nematocidal activity results indicated that some of them exhibited good control efficacy against the tomato root-knot nematode disease caused by M. incognita. The docking results indicated that compound 6n interacts with amino acid residue Trp 279 of Ach E via hydrogen bond and amino acid residue Trp 84 of Ach E via π-π interaction.展开更多
[ Objective] The paper was to study the insecticidal activity and field efficacy of cyhalediamide, a novel insecticide developed by Zhejiang Research Institute of Chemical Industry, Ltd. [ Method] Toxicity of cyhalodi...[ Objective] The paper was to study the insecticidal activity and field efficacy of cyhalediamide, a novel insecticide developed by Zhejiang Research Institute of Chemical Industry, Ltd. [ Method] Toxicity of cyhalodiamide against Plutella xylostella, Spodoptera exigua, Prodenia litura and Chilo suppressalis were tasted in the laboratory by leaf-dipping method, and the field efficacy of cyhalodiamide against P. xylostella, S. exigua, P. litura, Pieris rapae, C. suppressalis and Cnaphalocrocis medinalis was evaluated. [ Result] The LCs0 values of cyhalodiamide against P. xylostella, S. exigua, P. litura and C. suppressalis were 0. 046, 0.072, 0.071 and 1.95 mg/L, respectively, almost equivalent to that of flubendiamide and ehlorantraniliprole. The control efficacy of 20% Z4042 SC （30 g/hm2） against P. xylostella, S. exigua, P. litura and P. rapae was 90.1% - 96.3 % after spraying for 7 d, and its control efficacy against C. suppressalis and C. medinalis was 82.9% -90.5% after spraying for 15 d. No crop injury was observed at the test dosage. [Conclusion] The study provided reference for field control against Lepidoptera pests.展开更多
[Objective] The paper was to establish the method for quantitative analysis of glyphosate herbicide and identification of salt type. [Method] Using ion chromatographic column switching method,cations( sodion,ammonium ...[Objective] The paper was to establish the method for quantitative analysis of glyphosate herbicide and identification of salt type. [Method] Using ion chromatographic column switching method,cations( sodion,ammonium ion,potassium ion,dimethonium ion and isopropylamine ion) and glyphosate anion in glyphosate salt were determined with Thermo IonP ac SCS1 cation exchange column and Thermo IonP ac AS14 anion exchange column,and external standard method was used for quantification. [Result] Various components showed good linear relationship within the linearity range,and the correlation coefficient r was greater than 0. 999; the relative standard deviation of retention time and peak area were less than 0. 13% and 1. 22%,respectively; the recovery was 98. 22%-99. 97%.[Conclusion] The method is precise,accurate and simple,and can be used to determine the active ingredients of glyphosate herbicide.展开更多
Silicon(Si)particles were functionalized using carbon dots(CDs)to enhance the interaction between the Si particles and the binders.First,CDs rich in polar groups were synthesized using a simple hydrothermal method.The...Silicon(Si)particles were functionalized using carbon dots(CDs)to enhance the interaction between the Si particles and the binders.First,CDs rich in polar groups were synthesized using a simple hydrothermal method.Then,CDs were loaded on the Si surface by impregnation to obtain the functionalized Si particles(Si/CDs).The phases and microstructures of the Si/CDs were observed using Fourier-transform infrared reflection,X-ray diffraction,scanning electron microscopy,and high-resolution transmission electron microscopy.Si/CDs were used as the active material of the anode for electrochemical performance experiments.The electrochemical performance of the Si/CD electrode was assessed using cyclic voltammetry,electrochemical impedance spectroscopy,and constant current charge and discharge experiment.The electrodes prepared with Si/CDs showed good mechanical structure stability and electrochemical performance.After 150 cycles at 0.2 C,the capacity retention rate of the Si/CD electrode was 64.0%,which is twice as much as that of pure Si electrode under the same test conditions.展开更多
Ethylene chlorotrifluoroethylene(ECTFE)coating was applied to the surface of carbon steel through electrostatic spraying and low-temperature heat treatment.The morphology and structure of the coating were analyzed usi...Ethylene chlorotrifluoroethylene(ECTFE)coating was applied to the surface of carbon steel through electrostatic spraying and low-temperature heat treatment.The morphology and structure of the coating were analyzed using various characterization techniques.The electrochemical data of the coated steel soaked in 3.5%(mass fraction)NaCl solution for 90 d at different periods were also examined.The findings indicate that the outer surface of the coating remains structurally stable before and after soaking.F can diffuse into the steel substrate,facilitating the bonding between the coating and the steel substrate,but the free F also induces a weakening effect on the crystalline structure.Due to the thickness of the coating edge and the susceptibility to infiltration of the corrosive medium,under-film micro-zone corrosion occurs at a slow rate.After soaking for 90 d,the impedance modulus measures approximately 10^(4)Ω·cm^(2),and the open circuit potential(OCP)is−0.61 V.The self-corrosion current density is 1.13×10^(−6)A/cm^(2),resulting in a calculated coating protection rate of 99.29%.In summary,despite edge corrosion occurring,the ECTFE coating provides excellent corrosion protection.展开更多
Microchannel flow boiling heat transfer has the advantages of strong heat dissipation capacity,good temperature uniformity,and compact structure.It is an excellent way to thermally manage electronic devices,but when t...Microchannel flow boiling heat transfer has the advantages of strong heat dissipation capacity,good temperature uniformity,and compact structure.It is an excellent way to thermally manage electronic devices,but when the heat flux exceeds CHF(Critical Heat Flux),the heat transfer performance deteriorates as the working fluid dries out.Non-azeotropic mixtures have the potential to effectively delay or avoid dry-out during the boiling process due to their temperature slide characteristics which causes the mass transfer resistance.To understand the influence of non-azeotropic mixtures on microchannel flow boiling,using the phase-change microchannel heat sink as the research object,the experiments on the flow boiling heat transfer performance of R245fa/R134a mixtures under different working conditions were carried out,and the characteristics of flow boiling heat transfer were obtained under the different working conditions,and comparison was developed with those of pure substance R245fa.The results demonstrated that a small amount of low-boiling-point components in the high-boiling-point working fluid inhibited boiling heat transfer to some extent,and lowered the average heat transfer coefficient under the non-dryout condition slightly lower than that of the pure substance;however,it also effectively delayed the onset of local dry-out and prevented significant deterioration in thermal transfer performance under the lower mass flow rate and higher heat flux,which could enhance the heat sink's stability.展开更多
A suitable mixing rule is important for vapor liquid equilibrium(VLE)investigations for mixed refrigerants.In this work,a new excess free energy mixing rule(MRv)was proposed at zero pressure based on the linear relati...A suitable mixing rule is important for vapor liquid equilibrium(VLE)investigations for mixed refrigerants.In this work,a new excess free energy mixing rule(MRv)was proposed at zero pressure based on the linear relationship between dimensionless parameter 1/(u-1)and a.MRv mixing rule was explicit adopted variable liquid molar volume.The applicable temperature range of MRv could be extended by means of an empirical method to estimate the liquid molar volume for components at high temperatures.Three mixing rules modified Huron-Vidal mixing rule(MHV1),Wong-Sandler mixing rule(WS),and MRv at two reference pressures were used to compare the VLE data in the calculation of 37 mixed refrigerants.Results demonstrated that MRv had a relatively similar accuracy to MHV1 and WS for component and pressure calculation.Moreover,the average excess Gibbs free energy using the MRv mixing rule for the 37 selected mixed refrigerants(0.0013)was much lower than those using the MHV1(0.0078)and WS(0.0809)mixing rules,which was very valuable for the design and optimization of thermodynamic systems using mixed refrigerants.展开更多
A series of novel 6-(/er/-butyl)-8-fluoro-2,3- dimethylquinoline carbonate derivatives were designed and synthesized. Bioassay results showed that some of them exhibited good activity against Pyricularia oryzae (P. or...A series of novel 6-(/er/-butyl)-8-fluoro-2,3- dimethylquinoline carbonate derivatives were designed and synthesized. Bioassay results showed that some of them exhibited good activity against Pyricularia oryzae (P. oryzae). It was found that the compound 5q (benzyl (6-(tert-butyl)-8-fluoro-2,3-dimethylquinolin-4-yl) carbonate) possessed good activity against P. oryzae whatever protective activity (10 mg·L^-1) or curative activity (25 mg·L^-1), which was better than that of control tebufloquin. In addition, the frontier molecular orbit results revealed that the compound held higher activity against P. oryzae when the total energy was low and the ClogP was high, which may provide useful information for further design novel fungicides.展开更多
Pyrazole carboxamide derivatives represent an important class of fungicides in agrochemicals. To find more novel structural pyrazole carboxamides, a novel series of 3-（trifluoromethyl）-lH-pyrazole-4-carboxamide comp...Pyrazole carboxamide derivatives represent an important class of fungicides in agrochemicals. To find more novel structural pyrazole carboxamides, a novel series of 3-（trifluoromethyl）-lH-pyrazole-4-carboxamide compounds were prepared from ethyl 4,4,4-trifluoroace- toacetate and triethyl orthoformate as starting materials. All the products were characterized by Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance （NMR）, 13C NMR, 19F NMR and mass spectrography. The bioassay results showed these fluorine-containing pyrazole carboxamides have a weak fungicidal activity but some of them exhibit a good nematocidal activity against M. incognita.展开更多
After the Kigali Amendment(KA)came into effect,HCFC-22 plants are obliged to limit HFC-23 emissions.Therefore,the study of costeffective mitigation pathways for HFC-23 is important for the sustainable implementation o...After the Kigali Amendment(KA)came into effect,HCFC-22 plants are obliged to limit HFC-23 emissions.Therefore,the study of costeffective mitigation pathways for HFC-23 is important for the sustainable implementation of KA in China and other HCFC-22 producing countries.This study constructed an inventory of HFC-23 by-production,emissions,and abatement for HCFC-22 plants in China from 2006 to 2020,and predicted the costs and climate benefits of HFC-23 abatement in China's compliance with the KA between 2021 and 2060.Results showed that HFC-23 emissions from HCFC-22 plants in China contributed about 60%of the growth in global atmospheric mole fraction of HFC-23 observed by Advanced Global Atmospheric Gases Experiment(AGAGE)from 2007 to 2020.Furthermore,China's cumulative HFC-23 abatement was about 109 kt(1613 Mt CO_(2)-eq)from 2006 to 2019,accounting for 53%of total by-production,which allowed the global atmospheric mole fraction and radiative forcing of HFC-23 in 2020 to avoid an uplift of 9.2×10^(-9)and i.7 mW m^(-2),respectively,contributing to climate change mitigation.Under the baseline of the Kigali Amendment,less emission(LE),and resource utilization(RU)scenarios,the cumulative HFC-23 abatement from 2021 to 2060 would be 683±29 kt(10,107±431 Mt CO_(2)-eq),694±29 kt(10,277±427 Mt CO_(2)-eq),and 702±29 kt(10,385±426 Mt CO_(2)-eq),respectively.The cumulative net abatement costs for the KA,LE,and RU scenarios would be(5.0±0.2)billion,(2.9±0.2)billion,and(-2.7±0.2)billion CNY(2021 prices),respectively.In the future,applying resource utilization technology to reduce HFC-23 emissions can achieve both climate and economic benefits.展开更多
In order to discover new molecules with good insecticidal activities, a series of anthranilic diamides containing polyfluoroalkyl pyrazole were designed and synthesized, and their structures were characterized by1 H N...In order to discover new molecules with good insecticidal activities, a series of anthranilic diamides containing polyfluoroalkyl pyrazole were designed and synthesized, and their structures were characterized by1 H NMR and HRMS. Bioassays demonstrated that some of the title compound exhibited excellent insecticidal activities. The larvicidal activities of compound 8a, 8c, 8g, 8k and 8l against Mythimna separata Walker were 100% at 0.8 mg/L. The insecticidal activities of compound 8a, 8c,8e, 8g, 8k and 8l against Plutella xylostella Linnaeus were 100% at 0.4 mg/L. Surprisingly compounds 8a and 8c still showed 100% larvicidal activities against Plutella xylostella Linnaeus at 0.08 mg/L comparable to the commercialized Chlorantraniliprole. The LC_（50） of compound 8a and 8c against M. separata is 0.048 and 0.043 mg/L respectively.展开更多
Twenty six novel pyrimidin-4-amine derivatives containing the 1,2,4-oxadiazole motif were synthesized. Their chemical structures were confirmed by ^(1)H nuclear magnetic resonance (NMR), ^(13)C NMR, and high-resolutio...Twenty six novel pyrimidin-4-amine derivatives containing the 1,2,4-oxadiazole motif were synthesized. Their chemical structures were confirmed by ^(1)H nuclear magnetic resonance (NMR), ^(13)C NMR, and high-resolution mass spectrography. The insecticidal activity results indicated that some of them possessed excellent insecticidal activity (100%) against Mythimna separate, especially for compounds 6d, 6f, 6o, 6w, 6y and 6z. These compounds exhibited no activity against the insects Aphis medicagini and Tetranychus cinnabarinus. The structure- insecticidal activity relationships are discussed. Density functional theory analysis can potentially be used to design more active compounds. These results provide useful insecticide design information for further optimization.展开更多
In this work, with excellent environmental characteristics and thermodynamic properties, R161 is considered as a drop-in replacement of R407C used in small-scale air conditioning systems. In order to study the potenti...In this work, with excellent environmental characteristics and thermodynamic properties, R161 is considered as a drop-in replacement of R407C used in small-scale air conditioning systems. In order to study the potential of R161 in the application, the theoretical and experimental cycle performances of R161 and R407C were compared under different working conditions. The experimental results agreed well with theoretical results. In the experiment, COPs of R161 were about 15% higher than those of R407C. The compressor power consumptions of R161 were about 18% lower than those of R407C. The discharge temperatures of R161 were about 0-4℃ lower than those of R407C. Besides, the annual electric consumption of a small-scale split air conditioning in Beijing, Shanghai and Hongkong could be reduced by about 19.5%, when the working fluid was changed from R407C to R161. Overall, the results indicated that R161 has a better cycle performance and good compatibility with the existing systems designed for R407C.展开更多
Electrocaloric(EC)refrigeration holds the promise to achieve next-generation refrigeration technology that can be efficiently powered by electricity.BaTiO_(3)(BT)-based ferroelectric materials are attractive owing to ...Electrocaloric(EC)refrigeration holds the promise to achieve next-generation refrigeration technology that can be efficiently powered by electricity.BaTiO_(3)(BT)-based ferroelectric materials are attractive owing to their environmentally benign compositions,large polarization,and existing manufacturing method for multilayer ceramic capacitors(MLCC),which have stimulated intensive research efforts on these materials.Here,we report an enhanced electrocaloric effect(ECE)and the refrigeration capacity of multi-element B-site substituted BT-based ceramics.The compositions of the proposed Ba(Hf_(x)Sn_(x)Zr_(y))-Ti_(1-2x-y)O_(3)(BHSZT)ceramics were selected by fine-tuning each substituent against Titanium ions Ti^(4+),aiming to their respective morphotropic phase boundary(MPB).The BHSZT exhibited an ECE that is greater than that of the single-element substituted BaTiO_(3) ceramics by at least 50%,reaching an adiabatic temperature change of above 1.7 K under 40 kV/cm.Meanwhile,the operating temperature window of the BHSZT ceramics is observed to cover the room temperature,which is a critical feature that allows the device implementation in our daily life.The multi-element substitution improved the overall ECE performances,providing a high degree of freedom for polar reorientation and hence the large polar entropy that could be utilized by the external electric field.展开更多
基金financially supported by the National Nature Science Foundations of China (Nos. 52002157 and 51873083)the Nature Science Foundations of Jiangsu Province, China (No. BK20190976)
文摘Cost-effective,safe,and highly performing energy storage devices require rechargeable batteries,and among various options,aqueous zinc-ion batteries(ZIBs)have shown high promise in this regard.As a cathode material for the aqueous ZIBs,manganese dioxide(MnO_(2))has been found to be promising,but certain drawbacks of this cathode material are slow charge-transfer capability and poor cycling performance.Herein,a novel design of graphene quantum dots(GQDs)integrated with Zn-intercalated MnO_(2)nanosheets is put forward to construct a 3D nanoflower-like GQDs@ZnxMnO_(2)composite cathode for aqueous ZIBs.The synergistic coupling of GQDs modification with Zn intercalation provides abundant active sites and conductive medium to facilitate the ion/electron transmission,as well as ensure the GQDs@ZnxMnO_(2)composite cathode with enhanced charge-transfer capability and high electrochemical reversibility,which are elucidated by experiment results and in-situ Raman investigation.These impressive properties endow the GQDs@ZnxMnO_(2)composite cathode with superior aqueous Zn^(2+) storage capacity(~403.6 mAh·g^(−1)),excellent electrochemical kinetics,and good structural stability.For actual applications,the fabricated aqueous ZIBs can deliver a substantial energy density(226.8 W·h·kg^(−1)),a remarkable power density(650 W·kg^(−1)),and long-term cycle performance,further stimulating their potential application as efficient electrochemical storage devices for various energy-related fields.
基金supported by Zhejiang Provincial Science Foundation of China(No.LY16C140007)
文摘A series of novel 1-methyl-3-（trifluoromethyl）-^1H-pyrazole-4-carboxamide derivatives were designed based on our previous work and synthesized. All these title compounds were confirmed by NMR and MS. The primarily nematocidal activity results indicated that some of them exhibited good control efficacy against the tomato root-knot nematode disease caused by M. incognita. The docking results indicated that compound 6n interacts with amino acid residue Trp 279 of Ach E via hydrogen bond and amino acid residue Trp 84 of Ach E via π-π interaction.
基金Supported by"Twelfth Five-Year"National Science and Technology Support Program(2011BAE06B01-20)
文摘[ Objective] The paper was to study the insecticidal activity and field efficacy of cyhalediamide, a novel insecticide developed by Zhejiang Research Institute of Chemical Industry, Ltd. [ Method] Toxicity of cyhalodiamide against Plutella xylostella, Spodoptera exigua, Prodenia litura and Chilo suppressalis were tasted in the laboratory by leaf-dipping method, and the field efficacy of cyhalodiamide against P. xylostella, S. exigua, P. litura, Pieris rapae, C. suppressalis and Cnaphalocrocis medinalis was evaluated. [ Result] The LCs0 values of cyhalodiamide against P. xylostella, S. exigua, P. litura and C. suppressalis were 0. 046, 0.072, 0.071 and 1.95 mg/L, respectively, almost equivalent to that of flubendiamide and ehlorantraniliprole. The control efficacy of 20% Z4042 SC （30 g/hm2） against P. xylostella, S. exigua, P. litura and P. rapae was 90.1% - 96.3 % after spraying for 7 d, and its control efficacy against C. suppressalis and C. medinalis was 82.9% -90.5% after spraying for 15 d. No crop injury was observed at the test dosage. [Conclusion] The study provided reference for field control against Lepidoptera pests.
基金Supported by Science and Technology Project of Zhejiang Province(2016C37034)
文摘[Objective] The paper was to establish the method for quantitative analysis of glyphosate herbicide and identification of salt type. [Method] Using ion chromatographic column switching method,cations( sodion,ammonium ion,potassium ion,dimethonium ion and isopropylamine ion) and glyphosate anion in glyphosate salt were determined with Thermo IonP ac SCS1 cation exchange column and Thermo IonP ac AS14 anion exchange column,and external standard method was used for quantification. [Result] Various components showed good linear relationship within the linearity range,and the correlation coefficient r was greater than 0. 999; the relative standard deviation of retention time and peak area were less than 0. 13% and 1. 22%,respectively; the recovery was 98. 22%-99. 97%.[Conclusion] The method is precise,accurate and simple,and can be used to determine the active ingredients of glyphosate herbicide.
基金financially supported by the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang,China(No.2019R01006)the National Key R&D Program of China(Grant No.2018YFB0104300).
文摘Silicon(Si)particles were functionalized using carbon dots(CDs)to enhance the interaction between the Si particles and the binders.First,CDs rich in polar groups were synthesized using a simple hydrothermal method.Then,CDs were loaded on the Si surface by impregnation to obtain the functionalized Si particles(Si/CDs).The phases and microstructures of the Si/CDs were observed using Fourier-transform infrared reflection,X-ray diffraction,scanning electron microscopy,and high-resolution transmission electron microscopy.Si/CDs were used as the active material of the anode for electrochemical performance experiments.The electrochemical performance of the Si/CD electrode was assessed using cyclic voltammetry,electrochemical impedance spectroscopy,and constant current charge and discharge experiment.The electrodes prepared with Si/CDs showed good mechanical structure stability and electrochemical performance.After 150 cycles at 0.2 C,the capacity retention rate of the Si/CD electrode was 64.0%,which is twice as much as that of pure Si electrode under the same test conditions.
基金supported by the Zhejiang Postdoctoral Merit-Based Funding(No.ZJ2020030)the China Postdoctoral Science Foundation(No.2020M681920)the Zhejiang Sci-Tech University Youth Innovation Program(No.2021Q038),China.
文摘Ethylene chlorotrifluoroethylene(ECTFE)coating was applied to the surface of carbon steel through electrostatic spraying and low-temperature heat treatment.The morphology and structure of the coating were analyzed using various characterization techniques.The electrochemical data of the coated steel soaked in 3.5%(mass fraction)NaCl solution for 90 d at different periods were also examined.The findings indicate that the outer surface of the coating remains structurally stable before and after soaking.F can diffuse into the steel substrate,facilitating the bonding between the coating and the steel substrate,but the free F also induces a weakening effect on the crystalline structure.Due to the thickness of the coating edge and the susceptibility to infiltration of the corrosive medium,under-film micro-zone corrosion occurs at a slow rate.After soaking for 90 d,the impedance modulus measures approximately 10^(4)Ω·cm^(2),and the open circuit potential(OCP)is−0.61 V.The self-corrosion current density is 1.13×10^(−6)A/cm^(2),resulting in a calculated coating protection rate of 99.29%.In summary,despite edge corrosion occurring,the ECTFE coating provides excellent corrosion protection.
基金supported by the National Natural Science Foundation of China(No.52076185)the Natural Science Foundation of Zhejiang Province(No.LZ19E060001)the Open Project of Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering(No.KF2019-02)。
文摘Microchannel flow boiling heat transfer has the advantages of strong heat dissipation capacity,good temperature uniformity,and compact structure.It is an excellent way to thermally manage electronic devices,but when the heat flux exceeds CHF(Critical Heat Flux),the heat transfer performance deteriorates as the working fluid dries out.Non-azeotropic mixtures have the potential to effectively delay or avoid dry-out during the boiling process due to their temperature slide characteristics which causes the mass transfer resistance.To understand the influence of non-azeotropic mixtures on microchannel flow boiling,using the phase-change microchannel heat sink as the research object,the experiments on the flow boiling heat transfer performance of R245fa/R134a mixtures under different working conditions were carried out,and the characteristics of flow boiling heat transfer were obtained under the different working conditions,and comparison was developed with those of pure substance R245fa.The results demonstrated that a small amount of low-boiling-point components in the high-boiling-point working fluid inhibited boiling heat transfer to some extent,and lowered the average heat transfer coefficient under the non-dryout condition slightly lower than that of the pure substance;however,it also effectively delayed the onset of local dry-out and prevented significant deterioration in thermal transfer performance under the lower mass flow rate and higher heat flux,which could enhance the heat sink's stability.
基金supported by the Nation Natural Science Foundation of China(Grant No.52076185)the Natural Science Foundation of Zhejiang Province(No.LZ19E060001)。
文摘A suitable mixing rule is important for vapor liquid equilibrium(VLE)investigations for mixed refrigerants.In this work,a new excess free energy mixing rule(MRv)was proposed at zero pressure based on the linear relationship between dimensionless parameter 1/(u-1)and a.MRv mixing rule was explicit adopted variable liquid molar volume.The applicable temperature range of MRv could be extended by means of an empirical method to estimate the liquid molar volume for components at high temperatures.Three mixing rules modified Huron-Vidal mixing rule(MHV1),Wong-Sandler mixing rule(WS),and MRv at two reference pressures were used to compare the VLE data in the calculation of 37 mixed refrigerants.Results demonstrated that MRv had a relatively similar accuracy to MHV1 and WS for component and pressure calculation.Moreover,the average excess Gibbs free energy using the MRv mixing rule for the 37 selected mixed refrigerants(0.0013)was much lower than those using the MHV1(0.0078)and WS(0.0809)mixing rules,which was very valuable for the design and optimization of thermodynamic systems using mixed refrigerants.
基金Zhejiang Provincial Natural Science Foundation of China (No.LY16C140007)Research Institute Special Program of Department of Science and Technology of Zhejiang Province (No.2015F50030).
文摘A series of novel 6-(/er/-butyl)-8-fluoro-2,3- dimethylquinoline carbonate derivatives were designed and synthesized. Bioassay results showed that some of them exhibited good activity against Pyricularia oryzae (P. oryzae). It was found that the compound 5q (benzyl (6-(tert-butyl)-8-fluoro-2,3-dimethylquinolin-4-yl) carbonate) possessed good activity against P. oryzae whatever protective activity (10 mg·L^-1) or curative activity (25 mg·L^-1), which was better than that of control tebufloquin. In addition, the frontier molecular orbit results revealed that the compound held higher activity against P. oryzae when the total energy was low and the ClogP was high, which may provide useful information for further design novel fungicides.
文摘Pyrazole carboxamide derivatives represent an important class of fungicides in agrochemicals. To find more novel structural pyrazole carboxamides, a novel series of 3-（trifluoromethyl）-lH-pyrazole-4-carboxamide compounds were prepared from ethyl 4,4,4-trifluoroace- toacetate and triethyl orthoformate as starting materials. All the products were characterized by Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance （NMR）, 13C NMR, 19F NMR and mass spectrography. The bioassay results showed these fluorine-containing pyrazole carboxamides have a weak fungicidal activity but some of them exhibit a good nematocidal activity against M. incognita.
基金supported by the National Key Research and Development Program of China(2019YFC0214500)the Energy Foundation Beijing Representative Office in China.
文摘After the Kigali Amendment(KA)came into effect,HCFC-22 plants are obliged to limit HFC-23 emissions.Therefore,the study of costeffective mitigation pathways for HFC-23 is important for the sustainable implementation of KA in China and other HCFC-22 producing countries.This study constructed an inventory of HFC-23 by-production,emissions,and abatement for HCFC-22 plants in China from 2006 to 2020,and predicted the costs and climate benefits of HFC-23 abatement in China's compliance with the KA between 2021 and 2060.Results showed that HFC-23 emissions from HCFC-22 plants in China contributed about 60%of the growth in global atmospheric mole fraction of HFC-23 observed by Advanced Global Atmospheric Gases Experiment(AGAGE)from 2007 to 2020.Furthermore,China's cumulative HFC-23 abatement was about 109 kt(1613 Mt CO_(2)-eq)from 2006 to 2019,accounting for 53%of total by-production,which allowed the global atmospheric mole fraction and radiative forcing of HFC-23 in 2020 to avoid an uplift of 9.2×10^(-9)and i.7 mW m^(-2),respectively,contributing to climate change mitigation.Under the baseline of the Kigali Amendment,less emission(LE),and resource utilization(RU)scenarios,the cumulative HFC-23 abatement from 2021 to 2060 would be 683±29 kt(10,107±431 Mt CO_(2)-eq),694±29 kt(10,277±427 Mt CO_(2)-eq),and 702±29 kt(10,385±426 Mt CO_(2)-eq),respectively.The cumulative net abatement costs for the KA,LE,and RU scenarios would be(5.0±0.2)billion,(2.9±0.2)billion,and(-2.7±0.2)billion CNY(2021 prices),respectively.In the future,applying resource utilization technology to reduce HFC-23 emissions can achieve both climate and economic benefits.
基金supported by Key Projects of the National Science and Technology Pillar Program of China(No.2011BAE06B01-20)
文摘In order to discover new molecules with good insecticidal activities, a series of anthranilic diamides containing polyfluoroalkyl pyrazole were designed and synthesized, and their structures were characterized by1 H NMR and HRMS. Bioassays demonstrated that some of the title compound exhibited excellent insecticidal activities. The larvicidal activities of compound 8a, 8c, 8g, 8k and 8l against Mythimna separata Walker were 100% at 0.8 mg/L. The insecticidal activities of compound 8a, 8c,8e, 8g, 8k and 8l against Plutella xylostella Linnaeus were 100% at 0.4 mg/L. Surprisingly compounds 8a and 8c still showed 100% larvicidal activities against Plutella xylostella Linnaeus at 0.08 mg/L comparable to the commercialized Chlorantraniliprole. The LC_（50） of compound 8a and 8c against M. separata is 0.048 and 0.043 mg/L respectively.
基金funded by the Zhejiang Provincial Natural Science Foundation of China(Grant No.LY19C140002)the Company of Three Win(Grant No.KYY-HX-20200746)Research Fund of Department of Education of Zhejiang Province(Grant No.Y202043162).
文摘Twenty six novel pyrimidin-4-amine derivatives containing the 1,2,4-oxadiazole motif were synthesized. Their chemical structures were confirmed by ^(1)H nuclear magnetic resonance (NMR), ^(13)C NMR, and high-resolution mass spectrography. The insecticidal activity results indicated that some of them possessed excellent insecticidal activity (100%) against Mythimna separate, especially for compounds 6d, 6f, 6o, 6w, 6y and 6z. These compounds exhibited no activity against the insects Aphis medicagini and Tetranychus cinnabarinus. The structure- insecticidal activity relationships are discussed. Density functional theory analysis can potentially be used to design more active compounds. These results provide useful insecticide design information for further optimization.
基金supported by the National Natural Science Foundation of China(Grant No.51936007 and No.51576171)。
文摘In this work, with excellent environmental characteristics and thermodynamic properties, R161 is considered as a drop-in replacement of R407C used in small-scale air conditioning systems. In order to study the potential of R161 in the application, the theoretical and experimental cycle performances of R161 and R407C were compared under different working conditions. The experimental results agreed well with theoretical results. In the experiment, COPs of R161 were about 15% higher than those of R407C. The compressor power consumptions of R161 were about 18% lower than those of R407C. The discharge temperatures of R161 were about 0-4℃ lower than those of R407C. Besides, the annual electric consumption of a small-scale split air conditioning in Beijing, Shanghai and Hongkong could be reduced by about 19.5%, when the working fluid was changed from R407C to R161. Overall, the results indicated that R161 has a better cycle performance and good compatibility with the existing systems designed for R407C.
基金supported by the National Key R&D Program of China(Grant No.2020YFA0711500)the National Natural Science Foundation of China(Grant No.52076127)+5 种基金the Natural Science Foundation of Shanghai(Grant Nos.20ZR1471700,22JC1401800)supported by the State Key Laboratory of Mechanical System and Vibration(Grant No.MSVZD202211)the Oceanic Interdisciplinary Program of Shanghai Jiao Tong University(Grant No.SL2020MS009)the Prospective Research Program at Shanghai Jiao Tong University(Grant No.19X160010008)the Changzhou Leading Talents Projectthe Student Innovation Center and the Instrumental Analysis Center at Shanghai Jiao Tong University。
文摘Electrocaloric(EC)refrigeration holds the promise to achieve next-generation refrigeration technology that can be efficiently powered by electricity.BaTiO_(3)(BT)-based ferroelectric materials are attractive owing to their environmentally benign compositions,large polarization,and existing manufacturing method for multilayer ceramic capacitors(MLCC),which have stimulated intensive research efforts on these materials.Here,we report an enhanced electrocaloric effect(ECE)and the refrigeration capacity of multi-element B-site substituted BT-based ceramics.The compositions of the proposed Ba(Hf_(x)Sn_(x)Zr_(y))-Ti_(1-2x-y)O_(3)(BHSZT)ceramics were selected by fine-tuning each substituent against Titanium ions Ti^(4+),aiming to their respective morphotropic phase boundary(MPB).The BHSZT exhibited an ECE that is greater than that of the single-element substituted BaTiO_(3) ceramics by at least 50%,reaching an adiabatic temperature change of above 1.7 K under 40 kV/cm.Meanwhile,the operating temperature window of the BHSZT ceramics is observed to cover the room temperature,which is a critical feature that allows the device implementation in our daily life.The multi-element substitution improved the overall ECE performances,providing a high degree of freedom for polar reorientation and hence the large polar entropy that could be utilized by the external electric field.
