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Hydroxychloroquine and a low antiresorptive activity bisphosphonate conjugate prevent and reverse ovariectomy-induced bone loss in mice through dual antiresorptive and anabolic effects
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作者 Zhenqiang Yao Akram Ayoub +8 位作者 Venkatesan Srinivasan Jun Wu Churou Tang Rong Duan Aleksa Milosavljevic Lianping Xing Frank H.Ebetino Alison J.Frontier Brendan F.Boyce 《Bone Research》 SCIE CAS CSCD 2024年第3期734-744,共11页
Osteoporosis remains incurable.The most widely used antiresorptive agents,bisphosphonates(BPs),also inhibit bone formation,while the anabolic agent,teriparatide,does not inhibit bone resorption,and thus they have limi... Osteoporosis remains incurable.The most widely used antiresorptive agents,bisphosphonates(BPs),also inhibit bone formation,while the anabolic agent,teriparatide,does not inhibit bone resorption,and thus they have limited efficacy in preventing osteoporotic fractures and cause some side effects. 展开更多
关键词 res CONJUGATE phosphonate
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Aminated Cyclopropylmethylphosphonates as Potent Prostate Cancer Inhibitors
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作者 Abed Al Aziz Al Quntar Ibrahim Abasy 《Journal of Biosciences and Medicines》 2024年第7期239-244,共6页
Inspired by the anti-pancreatic promising results of our novel aminated cyclopropylmethylphosphonate compounds, an in vitro anti-prostate cancer activity exploration of these compounds was carried out on human prostat... Inspired by the anti-pancreatic promising results of our novel aminated cyclopropylmethylphosphonate compounds, an in vitro anti-prostate cancer activity exploration of these compounds was carried out on human prostate cancer cell line PC-3, and showed potent inhibiting activity at low micromolar concentrations (with an IC50 of approximately 45 μM). 展开更多
关键词 Prostate Cancer Cancer Cyclopropylphophonates AMINOphosphonateS CYCLOPROPANES phosphonateS Alkynylphosphonates ANTI-CANCER Prostate
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膦酸银配位聚合物电催化还原CO_(2)的性能
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作者 吴亚坤 毛晨 +2 位作者 李阳 高超颖 杨杨 《石油化工》 北大核心 2025年第2期167-172,共6页
采用水热合成法制备了一种具有三维网络结构的膦酸银配位聚合物Ag_(10)(H_(3)L)_(2)(H_(2)O)_(2)(4,4'-bipy),将其作为催化剂负载在碳布上制成工作电极,利用XRD,FTIR,TG等方法对催化剂进行了表征,并利用循环伏安法考察了催化剂的电... 采用水热合成法制备了一种具有三维网络结构的膦酸银配位聚合物Ag_(10)(H_(3)L)_(2)(H_(2)O)_(2)(4,4'-bipy),将其作为催化剂负载在碳布上制成工作电极,利用XRD,FTIR,TG等方法对催化剂进行了表征,并利用循环伏安法考察了催化剂的电催化还原CO_(2)的性能。实验结果表明,该催化剂具有良好结晶度、晶相纯度和热稳定性;在CO_(2)电化学还原反应中具有良好的催化活性和较高的电化学活性表面积,电化学活性表面积高达1014μF/cm^(2);在-1.0 V条件下,该催化剂能够维持较高的电催化CO_(2)还原稳定性,连续运行4 h时CO产物法拉第效率均超过90%。 展开更多
关键词 配位聚合物 膦酸银 电催化还原
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(2-乙基己基胺基)甲基膦酸单-2-乙基己基酯浸渍树脂对钪的选择性吸附及应用
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作者 杨剑峰 李艳玲 +2 位作者 韩经露 李松松 廖伍平 《应用化学》 北大核心 2025年第1期95-106,共12页
将(2-乙基己基胺基)甲基膦酸单-2-乙基己基酯(HEHAMP,H_(2)L_(2))浸渍到大孔树脂Pre-XAD-16上制得了浸渍树脂(SIRs-HEHAMP),研究了在硫酸介质中SIRs-HEHAMP对钪的吸附性能,考察了反应时间、溶液酸度、硫酸氢根离子浓度、树脂用量以及温... 将(2-乙基己基胺基)甲基膦酸单-2-乙基己基酯(HEHAMP,H_(2)L_(2))浸渍到大孔树脂Pre-XAD-16上制得了浸渍树脂(SIRs-HEHAMP),研究了在硫酸介质中SIRs-HEHAMP对钪的吸附性能,考察了反应时间、溶液酸度、硫酸氢根离子浓度、树脂用量以及温度等因素对钪吸附的影响,发现SIRs-HEHAMP浸渍树脂对Sc^(3+)的吸附量随着反应时间的增加而逐渐增大;在高酸度范围下,SIRs-HEHAMP浸渍树脂对Sc^(3+)的吸附率随着酸度的增大而略有降低,而在p H值范围内对Sc^(3+)的吸附率几乎没有影响;在吸附过程中硫酸氢根没有参与配位;温度对Sc^(3+)的吸附几乎没有影响;SIRs-HEHAMP吸附Sc^(3+)的过程符合准二级动力学模型;测定了浸渍树脂对钪的饱和负载量(以Sc_(2)O_(3)计)为36.29 mg/g,并对SIRs-HEHAMP浸渍树脂、HEHAMP萃取剂以及支撑基质Pre-XAD-16进行了红外光谱与TG-DSC表征,结果表明,HEHAMP成功浸渍到支撑基质Pre-XAD-16上。将SIRs-HEHAMP浸渍树脂用于从模拟赤泥浸出液中吸附和分离钪。Sc^(3+)的吸附率为51.71%,TiO^(2+)吸附率为42.50%,几乎不吸附Al^(3+),Fe^(3+)和稀土离子吸附率均在20%以下,Sc/Ti分离系数为1.45;加入质量分数为6%的H_(2)O_(2)时,SIRs-HEHAMP浸渍树脂对Sc^(3+)吸附率提升到63.17%,TiO^(2+)和Fe^(3+)的吸附率下降,其余金属离子基本不吸附,Sc/Ti分离系数提高至6.94,表明该浸渍树脂可以应用于从赤泥浸出液中分离回收钪。 展开更多
关键词 (2-乙基己基胺基)甲基膦酸单-2-乙基己基酯 浸渍树脂 吸附 分离
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有机膦酸盐缓凝剂异常增稠油井水泥浆作用机理
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作者 邹亦玮 代丹 +3 位作者 王义昕 耿晨梓 朱思佳 姚晓 《钻井液与完井液》 北大核心 2025年第1期110-116,共7页
有机膦酸盐是延长油井水泥浆中高温稠化时间的常用缓凝剂。通过讨论乙二胺四亚甲基膦酸钠(EDTMPS)缓凝剂对G级高抗硫(HSR)油井水泥浆稠化性能的影响,研究了EDTMPS掺量对4种不同厂家水泥稠化性能的影响。使用水化热、XRD和溶解度实验研究... 有机膦酸盐是延长油井水泥浆中高温稠化时间的常用缓凝剂。通过讨论乙二胺四亚甲基膦酸钠(EDTMPS)缓凝剂对G级高抗硫(HSR)油井水泥浆稠化性能的影响,研究了EDTMPS掺量对4种不同厂家水泥稠化性能的影响。使用水化热、XRD和溶解度实验研究了EDTMPS缓凝剂在不同厂家油井水泥浆中的作用机理。结果表明,EDTMPS缓凝剂抑制了二水石膏的溶解,同时促进了C_(3)A溶解。失去二水石膏缓凝作用的C_(3)A快速水化,导致水泥浆初始稠度上升;而EDTMPS缓凝剂促进了半水石膏溶解,释放的SO_(4)^(2-)延缓了C_(3)A的水化作用。通过调整G级HSR油井水泥中C_(3)A和二水石膏/半水石膏的含量匹配关系,可以改善水泥与EDTMPS缓凝剂的配伍性。 展开更多
关键词 油井水泥 高温 有机膦酸盐 稠化性能 微观结构
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Enantioselective synthesis of chiral phosphonylated 2,3-dihydrofurans by copper catalyzed asymmetric formal [3+2] cycloaddition of propargylic esters with β-keto phosphonates 被引量:1
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作者 陈修帅 侯传金 +3 位作者 李晴 刘彦军 杨瑞丰 胡向平 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1389-1395,共7页
Copper catalyzed asymmetric formal [3+2] cycloaddition of propargylic esters toβ‐keto phospho‐nates for the synthesis of chiral phosphonylated 2,3‐dihydrofurans was developed. By using a bulky and structurally ri... Copper catalyzed asymmetric formal [3+2] cycloaddition of propargylic esters toβ‐keto phospho‐nates for the synthesis of chiral phosphonylated 2,3‐dihydrofurans was developed. By using a bulky and structurally rigid tridentate ketimine P,N,N ligand, a series of optically active phosphonylated 2,3‐dihydrofurans were prepared in high yield and up to 92%ee. 展开更多
关键词 Copper Asymmetric synthesis [3+2] Cycloaddition β-Keto phosphonates Phosphonylated 2 3-dihydrofurans
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芬顿法处理废水中氨基三亚甲基膦酸同步回收磷研究
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作者 于莹 黎佳茜 +4 位作者 任帅康 吴瑞 温硕钊 刘明亮 张娟娟 《环境工程技术学报》 北大核心 2025年第2期594-602,共9页
去除与回收工业废水中常用阻垢剂氨基三亚甲基膦酸(ATMP)对水体保护与磷(P)资源可持续利用具有重要意义。采用Fenton法对废水中ATMP进行处理,首先比较了硫酸亚铁(FeSO_(4))、过氧化氢(H_(2)O_(2))、Fenton法(FeSO_(4)+H_(2)O_(2))对ATM... 去除与回收工业废水中常用阻垢剂氨基三亚甲基膦酸(ATMP)对水体保护与磷(P)资源可持续利用具有重要意义。采用Fenton法对废水中ATMP进行处理,首先比较了硫酸亚铁(FeSO_(4))、过氧化氢(H_(2)O_(2))、Fenton法(FeSO_(4)+H_(2)O_(2))对ATMP的处理效果,并进一步探究Fenton法处理ATMP体系中FeSO_(4)浓度、H_(2)O_(2)浓度、溶液初始pH、ATMP初始浓度以及共存离子等因素对ATMP处理效果的影响。结果表明:在ATMP初始浓度为1.0 mmol/L(以P计),采用Fenton法(FeSO_(4)和H_(2)O_(2)投加量均为1.5 mmol/L),溶液初始p H为3的反应条件下,ATMP的氧化处理效果较好,反应30 min后,体系中总磷(TP)去除率能达到95%,且去除的TP以磷酸铁(FePO_(4))沉淀的形式生成从而实现P回收。共存金属阳离子(Ca^(2+)或Mg^(2+))对ATMP的氧化降解无影响,共存无机阴离子(HCO_(3)^(-)或NO_(3)^(-))和共存有机阴离子(C_(5)H_(7)O_(5)COO^(-)或CH_(3)COO^(-))对体系中TP去除有抑制作用。自由基淬灭实验和电子自旋共振波谱测试结果表明,羟基自由基在Fenton法氧化处理ATMP的过程中起着关键性作用。综上所述,Fenton法可以有效实现对ATMP的氧化并最终生成正磷酸盐(PO_(4)^(3-)),同时在特定条件下PO_(4)^(3-)与三价铁离子结合生成FePO_(4)沉淀,实现P的资源化回收。本研究可为含有机膦酸盐ATMP废水的资源化处理提供参考。 展开更多
关键词 氨基三亚甲基膦酸(ATMP) 芬顿(Fenton) 磷回收 磷酸铁 羟基自由基
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Phosphonate-derived nitrogen-doped cobalt phosphate/carbon nanotube hybrids as highly active oxygen reduction reaction electrocatalysts 被引量:6
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作者 Hui Zhao Chen-Chen Weng +3 位作者 Jin-Tao Ren Li Ge Yu-Ping Liu Zhong-Yong Yuan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第2期259-267,共9页
The exploration of cost-effective non-noble-metal electrocatalysts is highly imperative to replace the state-of-the-art platinum-based catalysts for oxygen reduction reaction(ORR). Here, we prepared cobalt phosphonate... The exploration of cost-effective non-noble-metal electrocatalysts is highly imperative to replace the state-of-the-art platinum-based catalysts for oxygen reduction reaction(ORR). Here, we prepared cobalt phosphonate-derived N-doped cobalt phosphate/carbon nanotube hybrids(Co Pi C-N/CNTs) by hydrothermal treatment of N-containing cobalt phosphonate and oxidized carbon nanotubes(o-CNT) followed by high-temperature calcination under nitrogen atmosphere. The resultant Co Pi C-N/CNT exhibits a superior electrocatalytic performance for the ORR in alkaline media, which is equal to the commercial Pt/C catalyst in the aspect of half-wave potential, onset potential and diffuse limiting current density. Furthermore, the excellent tolerance to methanol and strong durability outperform those of commercial Pt/C. It is found that cobalt phosphonate-derived N-doped cobalt phosphate and the in-situ formed graphitic carbons play key roles on the activity enhancement. Besides, introducing a suitable amount of CNTs enhances the electronic conductivity and further contributes to the improved ORR performance. 展开更多
关键词 Metal phosphonate Metal phosphate Carbon nanotubes Oxygen reduction reaction ELECTROCATALYSIS
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固相萃取结合液相色谱串联质谱法测定生咖啡中草甘膦和氨甲基膦酸残留
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作者 毛静春 罗发美 +5 位作者 周琴 祁正有 曾侣斌 朱臆霖 王丽芳 程龙 《山西农业科学》 2025年第1期151-159,共9页
为了给咖啡种植过程中草甘膦农药使用提供指导,需建立一种分析生咖啡中草甘膦和氨甲基膦酸残留的检测方法。生咖啡粉末样品室温下经水超声提取,二氯甲烷萃取部分脂溶性组分,上清液用PCX固相萃取小柱净化,净化液与氯甲酸-9-芴基甲酯发生... 为了给咖啡种植过程中草甘膦农药使用提供指导,需建立一种分析生咖啡中草甘膦和氨甲基膦酸残留的检测方法。生咖啡粉末样品室温下经水超声提取,二氯甲烷萃取部分脂溶性组分,上清液用PCX固相萃取小柱净化,净化液与氯甲酸-9-芴基甲酯发生衍生化反应,液相色谱–串联质谱仪在正离子模式下扫描分析草甘膦和氨甲基膦酸衍生产物,内标法定量。采用固相萃取结合液相色谱串联质谱法检测生咖啡中草甘膦和氨甲基膦酸残留,结果表明,草甘膦和氨甲基膦酸在2~100 ng/mL呈良好线性关系,在0.05、0.10、0.20 mg/kg的加标水平下,平均回收率为81.8%~97.5%,相对标准偏差均小于9.1%,草甘膦和氨甲基膦酸的定量限均为0.04 mg/kg。采用此方法参加FAPAS(19377)能力验证,Z值为-0.4,结果满意。综上,该方法具有良好的线性关系,准确度和精密度均满足定量分析的要求,适用于生咖啡中草甘膦和氨甲基膦酸残留的定量分析。 展开更多
关键词 生咖啡 固相萃取 草甘膦 氨甲基膦酸 液相色谱串联质谱
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Adsorption mechanism of styryl phosphonate ester as collector in ilmenite flotation 被引量:3
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作者 Yan-ling XU Kai-hua HUANG +3 位作者 Hong-qiang LI Wei HUANG Cheng LIU Si-yuan YANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第12期4088-4098,共11页
A styryl phosphonate ester(SPE) collector was used to improve the flotation performance of ilmenite, and the adsorption mechanism and model were revealed and established, respectively. Microflotation tests showed that... A styryl phosphonate ester(SPE) collector was used to improve the flotation performance of ilmenite, and the adsorption mechanism and model were revealed and established, respectively. Microflotation tests showed that SPE exhibited a stronger collecting ability for ilmenite than the traditional collector styrene phosphonic acid(SPA). Zeta potential measurements revealed that both SPE and SPA could negatively shift the zeta potential of ilmenite, while SPE had more effects than SPA, suggesting the stronger adsorption of SPE. The analysis of X-ray photoelectron spectroscopy confirmed the chemisorption of SPA and SPE onto the Fe/Ti sites of ilmenite. According to frontier orbital theory, the chemical activities of SPE are greater than those of SPA. The partial densities of states analysis indicated that the PO—H groups of the collectors could interact with the Ti/Fe atoms of the ilmenite surface to generate a stable four-membered ring. The bonding model of the collector and(104) ilmenite surface showed that the adsorption energy of SPE was higher than that of SPA. Overall, SPE presented a better collecting ability and interaction effect for ilmenite flotation than SPA, and had the potential to replace SPA in the industry. 展开更多
关键词 styryl phosphonate ester ILMENITE FLOTATION COLLECTOR X-ray photoelectron spectroscopy density functional theory adsorption mechanism
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Highly efficient production of 2,5-dihydroxymethylfuran from biomass-derived 5-hydroxymethylfurfural over an amorphous and mesoporous zirconium phosphonate catalyst 被引量:2
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作者 Lei Hu Ning Li +4 位作者 Xiaoli Dai Yuqi Guo Yetao Jiang Aiyong He Jiaxing Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第10期82-92,共11页
The development of high-efficiency and low-cost catalysts is very crucial for the MeerweinPonndorf-Verley (MPV) reduction of biomass-derived 5-hydroxymethylfurfural (HMF) into 2,5-dihydroxymethylfuran (DHMF). In this ... The development of high-efficiency and low-cost catalysts is very crucial for the MeerweinPonndorf-Verley (MPV) reduction of biomass-derived 5-hydroxymethylfurfural (HMF) into 2,5-dihydroxymethylfuran (DHMF). In this work, an amorphous and mesoporous zirconium phosphonate catalyst (Zr-DTMP), which is a zirconium-containing organic-inorganic nanohybrid, was successfully designed and synthesized by the simple assembly of zirconium tetrachloride (ZrCl4) and diethylene triaminepenta(methylene phosphonic acid)(DTMP). Satisfactorily, when Zr-DTMP was employed for the MPV reduction of HMF in the presence of 2-butanol (secBuOH), DHMF yield could be achieved as 96.5% in 3 h under a relatively mild reaction temperature of 140℃. Systematic investigations indicated that this high catalytic activity should be mainly due to the cooperative role of enhancive Lewis acid site (Zr4+) and Lewis base site (O2-) in activating the carbonyl group of HMF and dissociating the hydroxyl group of secBuOH, respectively. Additionally, Zr-DTMP showed excellent catalytic stability, when it was successively used 5 recycles, its surface characteristics and textural properties still remained almost unchanged, and so, the catalytic activity was not obviously affected. More interestingly, Zr-DTMP could also be applied for the selective reduction of other biomass-derived carbonyl compounds, such as 5-methylfurfural (MF), furfural (FF), levulinic acid (LA), ethyl levulinate (EL) and cyclohexanone (CHN), into the corresponding products with high yields, which is beneficial to the effective synthesis of various valuable bio-based chemicals. 展开更多
关键词 5-HYDROXYMETHYLFURFURAL 2 5-Dihydroxymethylfuran 2-BUTANOL Zirconium phosphonate CATALYST Meerwein-Ponndorf-Verley reduction
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Synergistic effects of expandable graphite and dimethyl methyl phosphonate on the mechanical properties, fire behavior, and thermal stability of a polyisocyanurate-polyurethane foam 被引量:14
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作者 Hu Xiangming Wang Deming Wang Shuailing 《International Journal of Mining Science and Technology》 SCIE EI 2013年第1期13-20,共8页
In this study, a series of flame-retardant polyisocyanurate-polyurethane (PIR-PUR) foams were prepared using various concentrations (0-25% by weight) of expandable graphite (EG) and dimethyl methyl phosphonate (DMMP) ... In this study, a series of flame-retardant polyisocyanurate-polyurethane (PIR-PUR) foams were prepared using various concentrations (0-25% by weight) of expandable graphite (EG) and dimethyl methyl phosphonate (DMMP) (0-7% by weight). The effect of these additives on the properties of the PIR-PUR foams, including physico-mechanical, morphological, flame retardancy, and thermal stability, was studied. Increasing amounts of EG in the PIR-PUR foam caused a significant drop in the compression strength. However, DMMP caused the mechanical properties of PIR-PUR foam to improve compared to foam filled with EG alone. The flame retardancy of PIR-PUR foams containing both EG and DMMP was enhanced significantly compared to EG filled foams. Thermogravimetric analysis (TGA) indicated that EG enhances the thermal stability of PIR-PUR foams but that DMMP decreased it. The morphology of the residual char provided conclusive evidence for the weak thermal stability of foams filled with DMMP. 展开更多
关键词 Expandable graphite Dimethyl methyl phosphonate Fire behavior Thermal stability PIR–PUR foam
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SYNTHESIS, CHARACTERIZATION AND RING-OPENING POLYMERIZATION OF CYCLIC (ARYLENE PHOSPHONATE) OLIGOMERS 被引量:2
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作者 陈天禄 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2004年第1期83-89,共7页
A series of cyclic (arylene phosphonate) oligomers were prepared by reaction of phenylphosphonic dichloride (PPD) with various bisphenols under pseudo-high dilution conditions via interfacial polycondensation. The yie... A series of cyclic (arylene phosphonate) oligomers were prepared by reaction of phenylphosphonic dichloride (PPD) with various bisphenols under pseudo-high dilution conditions via interfacial polycondensation. The yield of cyclic (arylene phosphonate) oligomers is over 85% by using hexadecyltrimethylammoniun bromide as phase transfer catalyst (PTC) at 0 'C . The structures of the cyclic oligomers were confirmed by a combination of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and IR analysis. These cyclic oligomers undergo facile ring-opening polymerization in the melt by using potassium 4,4'-biphenoxide as the initiator to give linear polyphosphonate. Free-radical ring-opening polymerization of cyclic(arylene phosphonate) oligomers containing sulfur linkages was also performed in the melt using 2,2'-dithiobis(benzothiazole) (DTB) as the initiator at 270 °C and the resulting polymer had a Mw, of 8 × 103 with a molecular weight distribution of 4. Ring-opening copolymerization of these cyclic oligomers with cyclic carbonate oligomers was also achieved. The average molecular weight of the resulting copolymer is higher than the corresponding homopolymer and the thermal stability of the copolymer is better than the corresponding homopolymer. 展开更多
关键词 Cyclic(arylene phosphonate) oligomer Ring-opening polymerization COPOLYMER
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Synthesis,Structure and Characterization of a 3D Chiral Carboxylate and Phosphonate Metalorganic Framework Based on 1,1?-Biphenol Ligand 被引量:2
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作者 焦静静 李子建 +2 位作者 郑发鲲 刘百战 崔勇 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第9期1509-1515,共7页
A novel phosphonate-based chiral metal-organic framework 1 was synthesized from C2-symmetric 1,1?-biphenol-based ligand and structurally characterized by single-crystal and powder X-ray diffraction, Fourier-transform... A novel phosphonate-based chiral metal-organic framework 1 was synthesized from C2-symmetric 1,1?-biphenol-based ligand and structurally characterized by single-crystal and powder X-ray diffraction, Fourier-transform infrared spectra(FTIR), circular dichroism(CD) and thermogravimetric analyses(TGA). Two neighboring Mn ions are linked by two carboxylate groups and one phosphate group to form a di-manganese unit [Mn2] and each [Mn2] cluster in 1 is linked by five ligands, generating a 3D network with fns topology. In addition, the photoluminescence properties of 1 and H4 L were investigated. 展开更多
关键词 BIPHENOL phosphonate manganese chiral metal-organic framework photoluminescence
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Luminescence study of europium(III) tris(β-diketonato)/phosphonate complexes in chloroform 被引量:1
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作者 Stefan Lis Zbigniew Piskula +3 位作者 Krzysztof Staninski Sayaka Tamaki Masayuki Inoue Yuko Hasegawa 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第2期185-191,共7页
The extraction of Eu(Ⅲ) with β-diketone, HA, and monodentate or bidentate Lewis bases, B, into chloroform and the luminescence properties of the extracted species were studied. Pivaloyltrifluoroacetone, Hpta, and ... The extraction of Eu(Ⅲ) with β-diketone, HA, and monodentate or bidentate Lewis bases, B, into chloroform and the luminescence properties of the extracted species were studied. Pivaloyltrifluoroacetone, Hpta, and 2-thenoyltfifluoroacetone, Htta, were used as the β-diketones. The Lewis bases, B, were tetraethyl methylene diphosphonate, POPO, which was bidentate, and diethyl benzylphosphonate, PhPO which was monodentate. Based on the extraction data, the stability constants, log β, of the first complexes between tfis(β-diketonato)Eu(Ⅲ) and the phosphonate, EuA3B, were determined to be 6.0 for the POPO complex and 3.40 for the PhPO complex. The Eu(Ⅲ) luminescence intensity in the EuA3POPO was larger than EuA3 where A was either pta or tta at similar concentrations of Eu(Ⅲ), while that in Eu(pta)3PhPO was stronger than EuA3; however, in Eu(tta)3PhPO, it was weaker than Eu(tta)3. The POPO functions as a sensitizer, and the PhPO functions as a quencher for the tta chelate and as a sensitizer for the pta chelate. From the lifetime and quantum yield, φ, of the Eu(Ⅲ) luminescence in the complexes as well as the observation of the extractability of Eu(Ⅲ) with the Hpta and the phosphonates and of the luminescence spectra of the complexes, it was confirmed that the extraction of Eu(Ⅲ) was remarkably enhanced with a β-diketonate and a strong Lewis base, and also the ternary complex that was formed as the extracted species, showed luminescence enhancement. This phenomenon may be due the formation of a strong bond between the Eu(Ⅲ) and the strong Lewis base leading to more hydrophobicity in the extracted species and also to more effective energy transfer from the Lewis base to the Eu(Ⅲ). It was not significant whether the donor atoms were N or O. 展开更多
关键词 tris(β-diketonato)Eu(Ⅲ) extraction LUMINESCENCE phosphonate ligands rare earths
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Facile Synthesis and Adsorption Properties of Phosphonated Cellulose Beads for Selective Removal of Low-density Lipoprotein 被引量:1
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作者 Hao Feng YU Guo Qi FU Li LIU Bing Lin HE 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第9期1193-1196,共4页
A novel low-density lipoprotein adsorbent was prepared simply by directly phosphonating porous cellulose beads. Tests in vitro demonstrated that this adsorbent showed quite good adsorption performance for selective re... A novel low-density lipoprotein adsorbent was prepared simply by directly phosphonating porous cellulose beads. Tests in vitro demonstrated that this adsorbent showed quite good adsorption performance for selective removal of low-density lipoprotein from human plasma. The effects of preparation conditions on the lipoprotein sorption properties of the resulted adsorbent were investigated. The adsorption dynamics was also examined. 展开更多
关键词 Cellulose beads PHOSPHONATION low-density lipoprotein ADSORPTION HYPERLIPEMIA
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Hierarchical cobalt phenylphosphonate nanothorn flowers for enhanced electrocatalytic water oxidation at neutral pH 被引量:1
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作者 Mei-Rong Liu Yang-Peng Lin +3 位作者 Kai Wang Shumei Chen Fei Wang Tianhua Zhou 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第10期1654-1662,共9页
Cobalt-based phosphate/phosphonates are a class of promising water oxidation catalysts at neutralpH.Herein,we reported a facile hydrothermal synthesis of various nanostructured cobalt phe-nylphosphonates.It is found t... Cobalt-based phosphate/phosphonates are a class of promising water oxidation catalysts at neutralpH.Herein,we reported a facile hydrothermal synthesis of various nanostructured cobalt phe-nylphosphonates.It is found that the number of hydroxyl group of structure-directing reagent iscrucial for the construction of 3D hierarchical structures including hierarchical nanosheet flow-er-like assemblies and nanothorn microsphere.These samples were characterized by scanningelectron microscopy,transmission electron microscopy,X-ray diffraction,infrared,and X-ray pho-toelectron spectroscopy techniques.They can act as highly efficient electrocatalysts for the oxygenevolution reaction at neutral pH.Among these,hierarchical cobalt phenylphosphonate nanothornflowers present excellent performance,affording a current density of 1 mA cm^-2 required a smalloverpotential of 393 mV.This work offers a new clue to develop high-performance metal phospho-nate/phosphate catalysts toward electrochemical water oxidation. 展开更多
关键词 PHOSPHATE Morphology ELECTROCATALYSIS Neutral pH Oxygen evolution reaction phosphonateS
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Phosphonated USY,a promising catalyst for the development of environmentally benign biodiesel(methyl acetate) process 被引量:1
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作者 Kakasaheb Y.Nandiwale Gahana Gopal.C Vijay V.Bokade 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第3期285-290,共6页
The present study focuses on the evaluation of the potential applicability of Ultra Stable Y(USY) and phosphonated USY(1 wt%-4 wt%phosphorous loading) as heterogeneous catalysts for biodiesel(methyl acetate) pro... The present study focuses on the evaluation of the potential applicability of Ultra Stable Y(USY) and phosphonated USY(1 wt%-4 wt%phosphorous loading) as heterogeneous catalysts for biodiesel(methyl acetate) production.The synthesized catalysts were characterized by powder X-ray diffraction(XRD),Brunaer-Emmett-Teller(BET) surface area,total acidity by temperature-programmed desorption of ammonia(TPD-NH3) and Fourier Transform Infrared(FTIR) spectra.The performances of catalysts were evaluated for the transesterification of butyl acetate with methanol(a model reaction in biodiesel production).In view to obtain a maximum yield of methyl acetate,the optimization of process parameters such as reactant molar ratio,catalyst loading,reaction temperature and reaction time was performed.All the phosphonated USY catalysts showed higher catalytic activity than the parent USY,which can be attributed to the increase of total acidity due to phosphonation.2 wt% P/USY(2% phosphorous loaded on USY) exhibited 92% methyl acetate yield with 100% selectivity,which was proved to be a potential catalyst for biodiesel production.The invented catalyst was found to be stable and reusable for five catalytic cycles,demonstrating that it might be a environmentally benign catalytic process. 展开更多
关键词 TRANSESTERIFICATION phosphonated USY methyl acetate BIODIESEL
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Design, synthesis and in vitro evaluation of L-amino acid esters prodrugs of acyclic nucleoside phosphonates as anti-HBV agent 被引量:1
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作者 Xiao Zhong Fu Sai Hong Jiang +2 位作者 Jian Xin Yu She Yang RU Yun Ji 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第7期817-819,共3页
A series of novel L-amino acid esters prodrugs of acyclic nucleoside phosphonates was synthesized and their anti-HBV activity was evaluated in HepG2 2.2.15 cells. Compound 1d exhibited more potent anti-HBV activity an... A series of novel L-amino acid esters prodrugs of acyclic nucleoside phosphonates was synthesized and their anti-HBV activity was evaluated in HepG2 2.2.15 cells. Compound 1d exhibited more potent anti-HBV activity and lower cytotoxicity than those of adefovir dipivoxil with EC50 and CC50 values of 0.207 μmol/L and 2530 μmol/L, respectively. 展开更多
关键词 Acyclic nucleoside phosphonates L-Amino acid PRODRUG Anti-HBV activity
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Synthesis and Structural Chemistry of Two Novel Transition Metal Organic Phosphonates 被引量:1
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作者 胡进 张汉辉 +4 位作者 曹彦宁 张春刚 张帅 陈义平 孙瑞卿 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第8期939-946,共8页
Two novel transition metal phosphonate compounds, [Co(H2BDPP)(phen)]n 1 (BDPP = p-O3PCH2(C6H4)CH2PO3, phen = 1,10-phenanthroline) and [Pb3(BCP)2]n 2 (BCP = OOC(C6H4)CH2PO3), have been synthesized and str... Two novel transition metal phosphonate compounds, [Co(H2BDPP)(phen)]n 1 (BDPP = p-O3PCH2(C6H4)CH2PO3, phen = 1,10-phenanthroline) and [Pb3(BCP)2]n 2 (BCP = OOC(C6H4)CH2PO3), have been synthesized and structurally determined by X-ray single-crystal diffraction. Compound 1 crystallizes in the monoclinic system, space group C2/c with a = 21.169(4), b = 12.001(2), c = 7.6211(15)A, β = 98.03(3)°, V= 1917.2(6)A^3, C20H18N2O6P2Co, Mr = 505.22, Z = 8, De= 1.737 g/cm^3, p = 1.107 mm^-1, F(000) = 1020, the final R= 0.0450 and wR = 0.1306 for 2072 observed reflections (I 〉 2σ(I). Compound 2 crystallizes in the monoclinic system, space group C2/c with a = 4.7167(9), b = 18.753(2), c = 22.781(3)A, β = 91.07(3)°, V= 2014.7(14)A^, C8H6O5PPb1.5, Mr = 523.88, Z = 8, Dc = 3.454 g/cm^3, p = 25.222 mm^-1, F(000) = 1856, the final R = 0.0441 and wR = 0.1906 for 2259 observed reflections (I 〉 2σ(I). In compound 1, the 1D chain running along the c axis is bridged by four ligands (trans- HO3PCH2C6H4CH2PO3H) in four different directions to extend the structure into a three- dimensional network. In compound 2, the Pb(II) displays 4- and 5-coordination modes. There is a one-dimensional P-O-Pb band along the a axis formed by PO3 groups and Pb(II) cations. These bands are joined by μ2-O of -COO to yield two-dimensional inorganic P-O-Pb layers which are pillared by the OOCC6HaCH2PO3 ligands to form a three-dimensional network. Moreover, compound 2 displays a strong emission band attributed to the ligand-centered (LC) transition. 展开更多
关键词 transition metal organic phosphonate hydrothermal synthesis crystal structure
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