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Analysis of chloramphenicol in honey by on-line pretreatment liquid chromatography-tandem mass spectrometry 被引量:3
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作者 Shin-ichi Kawano Hong-Yuan Hao +1 位作者 Yuki Hashi Jin-Ming Lin 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第1期36-38,共3页
hloramphenicol is an antibiotic and one of the potential contaminants in honey.Solid-phase extraction is the key pretreatment procedure for analysis of chloramphenicol in honey.In this work,an on-line pretreatment liq... hloramphenicol is an antibiotic and one of the potential contaminants in honey.Solid-phase extraction is the key pretreatment procedure for analysis of chloramphenicol in honey.In this work,an on-line pretreatment liquid chromatography-tandem mass spectrometer system for sensitive,reliable and higher throughput analysis was developed.With the methylcellulose-immobilized reversed-phase column,sugars in a honey sample were efficiently removed in 1 min.As a result,the limit of quantitation of chloramphenicol was 20 pg/mL(0.2 μg/kg honey). 展开更多
关键词 on-line pretreatment Liquid chromatography-mass spectrometry CHLORAMPHENICOL HONEY
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Preliminary Study:Furfural Production from Oat Husks via Phosphorus-Containing Catalysts Catalyzed Hydrothermal Pretreatment in the Context of Biorefinery
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作者 Prans Brazdausks Maris Puke Guntis Sosins 《Journal of Renewable Materials》 2025年第4期719-730,共12页
Oat husks,a byproduct of oat milling operations with limited economic value,present a promising feedstock for biorefinery processes due to their chemical composition.This study investigates the conversion of C5 carboh... Oat husks,a byproduct of oat milling operations with limited economic value,present a promising feedstock for biorefinery processes due to their chemical composition.This study investigates the conversion of C5 carbohydrates in oat husks into furfural through hydrothermal pretreatment using various phosphate-based catalysts,including H3PO4,NH4H2PO4,NaH2PO4,KH2PO4,K2HPO4 and K3PO4 as catalyst.The catalysts’effectiveness in promoting furfural production was evaluated under identical hydrothermal conditions(treatment time for 60 min at a constant temperature of 170℃ and a catalyst amount).Continuous water steam was used to strip furfural from the reaction zone and minimize its degradation.Results indicated that H3PO4 was the most effective catalyst,achieving a furfural yield of 13.99 wt.%,which corresponds to approximately 57%of the theoretical yield.NH4H2PO4 also showed moderate effectiveness,while sodium and potassium phosphate salts were significantly less effective.A scanning electron microscope analysis shows that catalysts with lower pH may disrupt the oat husks external layer thus providing a higher C5 carbohydrates conversion rate into furfural.The chemical complexity of oat husk contributes to side reactions between its carbohydrates and lignin during the hydrothermal treatment.This results in an increase in acid-insoluble lignin and inorganic matter in the oat husk lignocellulosic residue,which can reduce the effectiveness of further cellulose saccharification by enzymatic hydrolysis. 展开更多
关键词 Oat husks hydrothermal pretreatment furfural BIOREFINERY
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Rapid Determination of Residual Quinolones in Honey Samples by Fast HPLC with an On-Line Sample Pretreatment System
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作者 Wei Du JianGuo Yao +1 位作者 YueQi Li Yuki Hashi 《American Journal of Analytical Chemistry》 2011年第2期200-205,共6页
A method of on-line pretreatment coupled to HPLC with fluorescence detection was developed and validated for the determination of nine quinolones in honey samples. This method simplified the complicated process of sam... A method of on-line pretreatment coupled to HPLC with fluorescence detection was developed and validated for the determination of nine quinolones in honey samples. This method simplified the complicated process of sample pretreatment and reduced sample treatment time. Recovery of the quinolones was between 92% - 101% for spiked honey samples. The limit of detection was 0.22 - 3.78 ng/mL (signal/noise ratio = 3). There was good linear correlation between HPLC peak area and concentration of the quinolones, with a linear range of 1.0 - 100.0 ng/mL and correlation coefficients >0.9997. The method proposed was validated for detecting quinolones in honey samples. 展开更多
关键词 ANTIBIOTICS High Performance Liquid CHROMATOGRAPHY (HPLC) HONEY on-line pretreatment QUINOLONES
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Role of tannin pretreatment in flotation separation of magnesite and dolomite 被引量:2
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作者 Xiufeng Gong Jin Yao +5 位作者 Jun Guo Bin Yang Haoran Sun Wanzhong Yin Yulian Wang Yafeng Fu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期452-461,共10页
Flotation separation of magnesite and its calcium-containing carbonate minerals is a difficult problem.Recently,new regulat-ors have been proposed for magnesite flotation decalcification,although traditional regulator... Flotation separation of magnesite and its calcium-containing carbonate minerals is a difficult problem.Recently,new regulat-ors have been proposed for magnesite flotation decalcification,although traditional regulators such as tannin,water glass,sodium carbon-ate,and sodium hexametaphosphate are more widely used in industry.However,they are rarely used as the main regulators in research because they perform poorly in magnesite and dolomite single-mineral flotation tests.Inspired by the limonite presedimentation method and the addition of a regulator to magnesite slurry mixing,we used a tannin pretreatment method for separating magnesite and dolomite.Microflotation experiments confirmed that the tannin pretreatment method selectively and largely reduces the flotation recovery rate of dolomite without affecting the flotation recovery rate of magnesite.Moreover,the contact angles of the tannin-pretreated magnesite and dolomite increased and decreased,respectively,in the presence of NaOl.Zeta potential and Fourier transform infrared analyses showed that the tannin pretreatment method efficiently hinders NaOl adsorption on the dolomite surface but does not affect NaOl adsorption on the magnesite surface.X-ray photoelectron spectroscopy and density functional theory calculations confirmed that tannin interacts more strongly with dolomite than with magnesite. 展开更多
关键词 tannin pretreatment selective inhibition flotation separation MAGNESITE DOLOMITE
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Multiple pretreatments can effectively improve the functionality of mesenchymal stem cells 被引量:2
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作者 Xin-Xing Wan Xi-Min Hu Kun Xiong 《World Journal of Stem Cells》 SCIE 2024年第2期58-63,共6页
In this editorial,we offer our perspective on the groundbreaking study entitled“Hypoxia and inflammatory factor preconditioning enhances the immunosup-pressive properties of human umbilical cord mesenchymal stem cell... In this editorial,we offer our perspective on the groundbreaking study entitled“Hypoxia and inflammatory factor preconditioning enhances the immunosup-pressive properties of human umbilical cord mesenchymal stem cells”,recently published in World Journal of Stem Cells.Despite over three decades of research on the clinical application of mesenchymal stem cells(MSCs),only a few therapeutic products have made it to clinical use,due to multiple preclinical and clinical challenges yet to be addressed.The study proved the hypoxia and inflammatory factor preconditioning led to higher immunosuppressive effects of MSCs without damaging their biological characteristics,which revealed the combination of inflammatory factors and hypoxic preconditioning offers a promising approach to enhance the function of MSCs.As we delve deeper into the intricacies of pretreat-ment methodologies,we anticipate a transformative shift in the landscape of MSC-based therapies,ultimately contributing to improved patient outcomes and advancing the field as a whole. 展开更多
关键词 Mesenchymal stem cells Inflammatory factor HYPOXIA pretreatment
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Research Progress of QuEChERS Pretreatment Technique in the Detection of Multiple Pesticide Residues 被引量:1
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作者 Bo LIU Dawei WANG +3 位作者 Yuhang GUO Xuehua WANG Lei WANG Yajuan SONG 《Agricultural Biotechnology》 2024年第2期10-11,37,共3页
The QuEChERS extraction technique is a pretreatment technique that has been rapidly applied in recent years and is widely used in the field of pesticide residues with many advantages. This technique is based on solid ... The QuEChERS extraction technique is a pretreatment technique that has been rapidly applied in recent years and is widely used in the field of pesticide residues with many advantages. This technique is based on solid phase extraction (SPE), which uses the interaction between adsorbent and impurities in the matrix to achieve the purpose of purification. The method has easier operation and better purification effect than SPE. In this paper, the research progress of the QuEChERS technique in pesticide residue detection in different fields in recent years and its future development were reviewed, hoping to provide reference for further development and utilization of the QuEChERS technique in pesticide residue detection in the future. 展开更多
关键词 QUECHERS pretreatment Pesticide residues Research progress
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STRONGLY CONVERGENT INERTIAL FORWARD-BACKWARD-FORWARD ALGORITHM WITHOUT ON-LINE RULE FOR VARIATIONAL INEQUALITIES
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作者 姚永红 Abubakar ADAMU Yekini SHEHU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期551-566,共16页
This paper studies a strongly convergent inertial forward-backward-forward algorithm for the variational inequality problem in Hilbert spaces.In our convergence analysis,we do not assume the on-line rule of the inerti... This paper studies a strongly convergent inertial forward-backward-forward algorithm for the variational inequality problem in Hilbert spaces.In our convergence analysis,we do not assume the on-line rule of the inertial parameters and the iterates,which have been assumed by several authors whenever a strongly convergent algorithm with an inertial extrapolation step is proposed for a variational inequality problem.Consequently,our proof arguments are different from what is obtainable in the relevant literature.Finally,we give numerical tests to confirm the theoretical analysis and show that our proposed algorithm is superior to related ones in the literature. 展开更多
关键词 forward-backward-forward algorithm inertial extrapolation variational inequality on-line rule
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Retinal ischemia-reperfusion injury and pretreatment with Lycium barbarum glycopeptide
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作者 Yan-Xia Wu Shuo Yin +3 位作者 Shan-Shan Song Xiang Liu Yu-Xuan Deng Xue-Jing Lu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第9期1599-1605,共7页
AIM:To investigate the antioxidant protective effect of Lycium barbarum glycopeptide(LbGP)pretreatment on retinal ischemia-reperfusion(I/R)injury(RIRI)in rats.METHODS:RIRI was induced in Sprague Dawley rats through an... AIM:To investigate the antioxidant protective effect of Lycium barbarum glycopeptide(LbGP)pretreatment on retinal ischemia-reperfusion(I/R)injury(RIRI)in rats.METHODS:RIRI was induced in Sprague Dawley rats through anterior chamber perfusion,and pretreatment involved administering LbGP via gavage for 7d.After 24h of reperfusion,serum alanine aminotransferase(ALT),aspartate aminotransferase(AST),and creatinine(CREA)levels,retinal structure,expression of Caspase-3 and Caspase-8,superoxide dismutase(SOD)activity,and malondialdehyde(MDA)in the retina were measured.RESULTS:The pretreatment with LbGP effectively protected the retina and retinal tissue from edema and inflammation in the ganglion cell layer(GCL)and nerve fiber layer(NFL)of rats subjected to RIRI,as shown by light microscopy and optical coherence tomography(OCT).Serum AST was higher in the model group than in the blank group(P=0.042),but no difference was found in ALT,AST,and CREA across the LbGP groups and model group.Caspase-3 expression was higher in the model group than in the blank group(P=0.006),but no difference was found among LbGP groups and the model group.Caspase-8 expression was higher in the model group than in the blank group(P=0.000),and lower in the 400 mg/kg LbGP group than in the model group(P=0.016).SOD activity was lower in the model group than in the blank group(P=0.001),and the decrease was slower in the 400 mg/kg LbGP group than in the model group(P=0.003).MDA content was higher in the model group than in the blank group(P=0.001),and lower in the 400 mg/kg LbGP group than in the model group(P=0.016).The pretreatment with LbGP did not result in any observed liver or renal toxicity in the model.CONCLUSION:LbGP pretreatment exhibits dosedependent anti-inflammatory,and antioxidative effects by reducing Caspase-8 expression,preventing declines of SOD activity,and decreasing MDA content in the RIRI rat model. 展开更多
关键词 retinal ischemia-reperfusion Lycium barbarum glycopeptide pretreatment ANTI-INFLAMMATORY ANTIOXIDATIVE RAT
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Technological advancements in millet dehulling and polishing process: An insight into pretreatment methods, machineries and impact on nutritional quality
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作者 Shagolshem Mukta Singh Jayasree Joshi T P.Srinivasa Rao 《Grain & Oil Science and Technology》 CAS 2024年第3期186-195,共10页
Millets are widely recognized for their nutritional significance;however, the methods employed for their processing are currently lacking. This article primarily focuses on the advanced technologies and progressions i... Millets are widely recognized for their nutritional significance;however, the methods employed for their processing are currently lacking. This article primarily focuses on the advanced technologies and progressions in millet dehulling and polishing. These technologies operate based on the fundamental principles of compression-shearing, abrasion-friction, and centrifugal-impact forces. Processing of millets can be challenging because of the physical characteristics and tight attachment of hull and bran to the endosperm. However, several dehullers have been designed to solve this problem for different kinds of millets. In addition, the nutritional and anti-nutritional characteristics undergo alterations due to both dehulling and polishing processes. These alterations are thoroughly examined and discussed in this article. Specifically, anti-nutrients such as tannins and phytate are predominantly found in the outer pericarp of the grain and experience a reduction after undergoing dehulling and polishing. The nutritional properties are also subjected to a reduction;however, this reduction can be mitigated by subjecting the grains to certain pretreatments before dehulling and polishing. These treatments serve to enhance dehulling efficiency and nutrient digestibility while simultaneously reducing the presence of anti-nutrients. Novel thermal and non-thermal methodologies such as microwave, hydrothermal, high-pressure processing, and ohmic heating can be employed for processing millets, thereby diminishing the loss of nutrients. Additional research can be carried out to investigate their impact on the dehulling and polishing of millets. 展开更多
关键词 MILLETS DEHULLING POLISHING pretreatment Novel thermal and non-thermal techniques
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Thermal pretreatment of willow branches impacts yield and pore development of activated carbon in subsequent activation with ZnCl_(2) via modifying cellulose structure
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作者 Linghui Kong Chao Li +7 位作者 Runxing Sun Shu Zhang Yi Wang Jun Xiang Song Hu Dong Wang Chuanjun Leng Xun Hu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期227-237,共11页
Development of pore structures of activated carbon(AC)from activation of biomass with ZnCl_(2) relies on content and structure of cellulose/hemicellulose in the feedstock.Thermal pretreatment of biomass could induce d... Development of pore structures of activated carbon(AC)from activation of biomass with ZnCl_(2) relies on content and structure of cellulose/hemicellulose in the feedstock.Thermal pretreatment of biomass could induce dehydration and/or aromatization to change the structure of cellulose/hemicellulose.This might interfere with evolution of structures of AC,which was investigated herein via thermal pretreatment of willow branch(WB)from 200 to 360℃and the subsequent activation with ZnCl_(2) at 550℃.The results showed that thermal pretreatment at 360℃(WB-360)could lead to substantial pyrolysis to form biochar,with a yield of 31.9%,accompanying with nearly complete destruction of cellulose crystals and remarkably enhanced aromatic degree.However,cellulose residual in WB-360 could still be activated to form AC-360 with specific surface area of 1837.9 m~2·g^(-1),which was lower than that in AC from activation of untreated WB(AC-blank,2077.8 m~2·g^(-1)).Nonetheless,the AC-200 from activation of WB-200 had more developed pores(2113.9 m~2·g^(-1))and superior capability for adsorption of phenol,due to increased permeability of ZnCl_(2) to the largely intact cellulose structure in WB-200.The thermal pretreatment did increase diameters of micropores of AC but reduced the overall yield of AC(26.8%for AC-blank versus 18.0%for AC-360),resulting from accelerated cracking but reduced intensity of condensation.In-situ infrared characterization of the activation showed that ZnCl_(2) mainly catalyzed dehydration,dehydrogenation,condensation,and aromatization but not cracking,suppressing the formation of derivatives of cellulose and lignin in bio-oil.The thermal pretreatment formed phenolic-OH and C=O with higher chemical innerness,which changed the reaction network in activation,shifting morphology of fibrous structures in AC-blank to“melting surface”in AC-200 or AC-280. 展开更多
关键词 Thermal pretreatment Activation with ZnCl_(2) Willow branch Activated carbon Biochar
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Zinc pretreatment for protection against intestinal ischemiareperfusion injury
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作者 Ming-Zhen Cheng Jia-Hao Luo +2 位作者 Xin Li Feng-Yong Liu Wei-Jie Zhou 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第12期3843-3856,共14页
BACKGROUND Intestinal ischemia-reperfusion(I/R)injury(II/RI)is a critical condition that results in oxidative stress,inflammation,and damage to multiple organs.Zinc,an essential trace element,offers protective benefit... BACKGROUND Intestinal ischemia-reperfusion(I/R)injury(II/RI)is a critical condition that results in oxidative stress,inflammation,and damage to multiple organs.Zinc,an essential trace element,offers protective benefits in several tissues during I/R injury,but its effects on intestinal II/RI remain unclear.METHODS C57BL/6 mice were pretreated with zinc sulfate(ZnSO4,10 mg/kg)daily for three days before I/R injury was induced via superior mesenteric artery occlusion(SMAO)and abdominal aortic occlusion(AAO)models.Tissue and serum samples were collected to evaluate intestinal,liver,and kidney damage using Chiu’s score,Suzuki score,and histopathological analysis.Caco-2 cells and intestinal organoids were used for in vitro hypoxia-reoxygenation injury models to measure reactive oxygen species(ROS)and superoxide dismutase(SOD)levels.RESULTS Zinc pretreatment significantly reduced intestinal damage in the SMAO and AAO models(P<0.001).The serum levels of liver enzymes(alanine aminotransferase,aspartate aminotransferase)and kidney markers(creatinine and urea)were lower in the zinc-treated mice than in the control mice,indicating reduced hepatic and renal injury.In vitro,zinc decreased ROS levels and increased SOD activity in Caco-2 cells subject to hypoxia-reoxygenation injury.Intestinal organoids pretreated with zinc exhibited enhanced resilience to hypoxic injury compared to controls.CONCLUSION Zinc pretreatment mitigates II/RI and reduces associated multiorgan damage.These findings suggest that zinc has potential clinical applications in protecting against I/R injuries. 展开更多
关键词 Intestinal ischemia-reperfusion injury Zinc pretreatment Reactive oxygen species Oxidative stress Intestinal organoids Caco-2 cells
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Effects of Ultrasound/Dilute H_2 SO_4 Pretreatment on Cellulase Activity of Corn Straw Liquid Fermentation 被引量:37
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作者 杨培周 姜绍通 +2 位作者 潘丽军 罗水忠 黄俊 《Agricultural Science & Technology》 CAS 2009年第6期20-22,共3页
[ Objective] The aim was to study pretreatment of ultrasound enhancing dilute H2SO4 on cellulase activity of corn straw liquid fermentation and explore the pretretment' s optimal conditions. [ Method ] By using ortho... [ Objective] The aim was to study pretreatment of ultrasound enhancing dilute H2SO4 on cellulase activity of corn straw liquid fermentation and explore the pretretment' s optimal conditions. [ Method ] By using orthogonal test, the pretretment of ultrasound enhancing dilute H2SO4 on corn straw was studied, then straw was fermented as the sole carbon source. Finally, the cellulase activity in extracellular fermentation broth was determined. [Result] The results showed that cellulase activity in extracellular broth was greatest under the conditions of acid bath time 3 h, acid concentration 3.5%, ultrasonic power 150 W, and ultrasonic time 5 h. They were FPA 15.82 U/ml, Cx 39.9 U/ml, 13-Giu 55.94 U/ml respectively. [ Conclusion] Under the above conditions, extracellular cellulase production has a high stability. 展开更多
关键词 Ultrasonic wave Dilute H2SO4 Corn straw pretreatment
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Surface pretreatment of Mg alloys prior to Al electroplating in TMPAC-AlCl_3 ionic liquids 被引量:5
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作者 柳泉 刘奎仁 +1 位作者 韩庆 涂赣峰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第9期2111-2116,共6页
It is difficult to directly electroplate Al on Mg alloys. The effects of pretreatment parameters on the corrosion resistance of films obtained on AZ31 Mg alloy surface were studied by using potentiodynamic polarizatio... It is difficult to directly electroplate Al on Mg alloys. The effects of pretreatment parameters on the corrosion resistance of films obtained on AZ31 Mg alloy surface were studied by using potentiodynamic polarization curves, to produce a compact interfacial layer as zinc-immersion deposition. After the substrate was pretreated under optimized conditions, aluminum was electrodeposited on AZ31 from TMPAC-AlCl3 room temperature ionic liquids. The depositions were characterized by scanning electron microscope equipped with energy dispersion X-ray. The results show that the traditional pretreatment of Mg alloys was successfully used for the Al-electroplating process from TMPAC-AlCl3 ionic liquids. The entire procedure includes alkaline cleaning, chemical pickling, surface activation (400 mL/L HF acid, 10 min), zinc-immersion (20 min) and anhydrous treatment. A relatively compact zinc-immersion film was prepared on the substrate surface. A silvery-colored satin aluminum deposition was obtained on AZ31 from TMPAC-AlCl3 using direct current plating. 展开更多
关键词 magnesium alloys ELECTROPLATING pretreatment procedure ALUMINUM ionic liquids
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Research status of carbonaceous matter in carbonaceous gold ores and bio-oxidation pretreatment 被引量:7
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作者 杨洪英 刘倩 +1 位作者 宋襄翎 董金奎 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第11期3405-3411,共7页
Carbonaceous gold mines are important refractory gold ores. The previous results demonstrate that the carbonaceous matter is mainly composed of elemental carbon, organic acid and hydrocarbons. The dissolved aurocyanid... Carbonaceous gold mines are important refractory gold ores. The previous results demonstrate that the carbonaceous matter is mainly composed of elemental carbon, organic acid and hydrocarbons. The dissolved aurocyanide complex is robbed by adsorption of carbonaceous matter, which is similar to activated carbon in cyanide leaching of gold. The pretreatment methods of carbonaceous gold ores were introduced, including high temperature roasting, bio-oxidation, chemical oxidation, competitive adsorption, barrier inhibition and microwave roasting. Recently, bio-oxidation was developed rapidly due to its advantages such as mild conditions, simple processes, low energy consumption and friendly environment. The known microorganisms related with bio-oxidation pretreatment mainly are chemolithotroph bacteria such as Thiobacillus ferrooxidans, Thiobacillus thiooxidans and Leptospirillum ferrooxidans. The researches on decomposing and passivating carbonaceous matter were commenced by Phanerochaete chrysosporium, Pseudomonadaceae and Streptomyces setonii. Finally, the main problems were analyzed and the application prospect of this technique was looked forward. 展开更多
关键词 carbonaceous gold ores carbonaceous matter pretreatment bio-oxidization research status
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Effects of Different Pretreatment Methods on Determination of Microelements in Feed 被引量:2
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作者 葛亚明 宁红梅 +4 位作者 李敬玺 刘俊伟 安志兴 魏继涛 侯向红 《Animal Husbandry and Feed Science》 CAS 2009年第3期15-18,共4页
[ Objective] To study the effects of different pretreatment methods on determination of microelement in feed and thus find the best pre treatment method for each microetement, t Method] The samples (concentrated feed... [ Objective] To study the effects of different pretreatment methods on determination of microelement in feed and thus find the best pre treatment method for each microetement, t Method] The samples (concentrated feeding stuff and fodder) were pretreated through throe methods, that is, dry incineration method, HNOs HCIO, wetdecomposition method and microwave digestion method. Then the content of seven kinds of mi croelement (AI, Ca, Cu, Fe, Mn, Se and Zn) was determined by inductively coupled plasma atomic emission spectrometer (ICPAES). I Result] These three methods were all suitable for the determination of Cu, Mn and Zn in concentrated feeding stuff and the determination of Cu and Ca in fodder. The content of Cu and Ca was higher in fodder detected by HNO3 HCIO, wetdecomposition method. The microwave digestion method was suitable for the determination of AI and Ca in concentrated feeding stuff and the determination of AI, Fe, Mn and Zn in fodder. The dry incinera tion method was fit for the determination of Fe in concentrated feeding stuff. [ Condusionl The content of different microelements should be deter mined after the feed is treated with different Ioretreatment methods. 展开更多
关键词 pretreatment methods Determination of microelements Inductively coupled plasma atomic emission spectrometry
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Dechromization and dealumination kinetics in process of Na_2CO_3-roasting pretreatment of laterite ores 被引量:2
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作者 郭强 曲景奎 +3 位作者 韩冰冰 魏广叶 张培育 齐涛 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第12期3979-3986,共8页
A novel process was proposed for the activation pretreatment of limonitic laterite ores by Na2CO3 roasting. Dechromization and dealumination kinetics of the laterite ores and the effect of particle size, Na2CO3-ore ma... A novel process was proposed for the activation pretreatment of limonitic laterite ores by Na2CO3 roasting. Dechromization and dealumination kinetics of the laterite ores and the effect of particle size, Na2CO3-ore mass ratio, and roasting temperature on Cr and Al extraction were studied. Experimental results indicate that the extraction rates of Cr and Al are up to 99%and 82%, respectively, under the optimal particle size of 44–74μm, Na2CO3-to-ore mass ratio of 0.6:1, and temperature of 1000 ℃. Dechromization within the range of 600–800 oC is controlled by the diffusion through the product layer with an apparent activation energy of 3.9 kJ/mol, and that it is controlled by the chemical reaction at the surface within the range of 900–1100 ℃ with an apparent activation energy of 54.3 kJ/mol. Besides, the Avrami diffusion controlled model with on apparent activation energy of 16.4 kJ/mol is most applicable for dealumination. Furthermore, 96.8%Ni and 95.6%Co could be extracted from the alkali-roasting residues in the subsequent pressure acid leaching process. 展开更多
关键词 dechromization DEALUMINATION KINETICS Na2CO3-roasting pretreatment laterite ore nickel cobalt
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Multi-Sensor Intelligent System for On-Line and Real-Time Moneitoring Tool Cutting State in FMS 被引量:1
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作者 徐春广 王信义 +1 位作者 邢济收 杨大勇 《Journal of Beijing Institute of Technology》 EI CAS 1997年第3期258-266,共9页
The principle and the constitution of an intelligent system for on-line and real-time montitoring tool cutting state were discussed and a synthetic sensors schedule combined a new type fluid acoustic emission sens... The principle and the constitution of an intelligent system for on-line and real-time montitoring tool cutting state were discussed and a synthetic sensors schedule combined a new type fluid acoustic emission sensor (AE) with motor current sensor was presented. The parallel communication between control system of machine tools, the monitoring intelligent system,and several decision-making systems for identifying tool cutting state was established It can auto - matically select the sensor way ,monitoring mode and identifying method in machining process- ing so as to build a successful and effective intelligent system for on -line and real-time moni- toring cutting tool states in FMS. 展开更多
关键词 tool cutting state on-line monitoring intelligent system acoustic emission sensor
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On-line机行血液透析滤过两种稀释模式效果的临床观察 被引量:2
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作者 易铁钢 祁爱蓉 程淑碧 《中国血液净化》 2004年第1期41-42,47,共3页
关键词 on-line 血液透析滤过 稀释模式 HDF 治疗 血液净化
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On-line hemodiafiltration技术和临床应用 被引量:25
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作者 谢红浪 季大玺 《肾脏病与透析肾移植杂志》 CAS CSCD 2005年第4期377-381,共5页
关键词 血液净化 肾脏疾病 临床 on-line 临床应用 肾脏替代治疗 终末期肾脏疾病 血液透析滤过 常规血液透析 生物相容性
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On-line血液透析滤过对移植肾功能延迟恢复的影响 被引量:1
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作者 余权星 刘强 +2 位作者 杜艺 李宓 彭莉 《中国血液净化》 2004年第4期192-193,200,共3页
目的 研究On -line血液透析滤过 (HDF)在移植肾功能延迟恢复患者中的应用。方法 我院2 0 0 2年 1月至 2 0 0 3年 7月肾移植术后发生移植肾功能延迟恢复患者 38例 ,2 9例采用Freseniuson -lineHDF透析机 ,F6 0透析器 ,透析滤过时间 3~... 目的 研究On -line血液透析滤过 (HDF)在移植肾功能延迟恢复患者中的应用。方法 我院2 0 0 2年 1月至 2 0 0 3年 7月肾移植术后发生移植肾功能延迟恢复患者 38例 ,2 9例采用Freseniuson -lineHDF透析机 ,F6 0透析器 ,透析滤过时间 3~ 4h ,血流量在 180~ 2 5 0ml/min ,置换液采取前稀释法 ,9例行HD治疗 ,采用GambroAK2 0 0透析机 ,F7透析器。结果  38例移植肾功能延迟恢复患者 ,2 9例用联机血液透析滤过 ,平均肾功能恢复时间为 ( 11.2± 5 .6 )天 ,治疗期间收缩压变化在 110~ 170mmHg,透析期间低血压发生率为 2 .6 % ,9例HD治疗者平均肾功能恢复时间为 ( 2 2 .3± 15 .7)天 ,透析期间低血压发生率为 13.2 %。结论 与HD比较 ,On -lineHDF对血压影响较小 ,可缩短移植肾功能恢复的时间。 展开更多
关键词 on-line血液透析 肾功能 肾移植 HDF
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