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烷基结构对MoDDPs摩擦磨损性能的影响
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作者 聂芊 吴春 李健 《润滑与密封》 CAS CSCD 北大核心 2002年第1期29-30,共2页
制备了不同碳原子数的伯、仲烷基MoDDPs,并研究了其油溶性,测定了其加入到100SN基础油中的抗磨性、减摩性和极压性。比较了烷基碳链的长短及伯、仲烷基不同结构对MoDDPs摩擦磨损性能的影响。结果表明仲烷基MoDDPs的摩擦磨损性能优于伯烷... 制备了不同碳原子数的伯、仲烷基MoDDPs,并研究了其油溶性,测定了其加入到100SN基础油中的抗磨性、减摩性和极压性。比较了烷基碳链的长短及伯、仲烷基不同结构对MoDDPs摩擦磨损性能的影响。结果表明仲烷基MoDDPs的摩擦磨损性能优于伯烷基MoDDPs。 展开更多
关键词 烷基结构 MoDDPs 摩擦磨损性能 润滑油添加剂
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基于Py-GC/MS分析的二烷基二硫代磷酸锌的烷基结构研究
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作者 吕七军 吕涯 《精细石油化工》 CAS CSCD 北大核心 2016年第4期56-60,共5页
利用裂解气质联用(Py-GC/MS)技术研究二烷基二硫代磷酸锌(ZDDP)的烷基结构。通过分析500℃试样的裂解气质图谱,得出主要的裂解产物为硫醇和烯烃,这些产物与试样的烷基结构有直接联系,从而推断出对应的烷基结构及相对含量比例。实验结果... 利用裂解气质联用(Py-GC/MS)技术研究二烷基二硫代磷酸锌(ZDDP)的烷基结构。通过分析500℃试样的裂解气质图谱,得出主要的裂解产物为硫醇和烯烃,这些产物与试样的烷基结构有直接联系,从而推断出对应的烷基结构及相对含量比例。实验结果表明:T202系列试样均含有正丁基、异辛基和正辛基,且相对含量n(正丁基)∶n(异辛基)∶n(正辛基)=1∶3∶2,T203和T204系列试样均含有异辛基和正辛基,n(异辛基)∶n(正辛基)=1∶1,T205系列试样均含有异辛基,异丙基和正辛基,n(异辛基)∶n(异丙基+正辛基)=1∶1,烷基种类与市场上ZDDP型号相一致。 展开更多
关键词 烷基二硫代磷酸锌 热裂解 烷基结构 Py-GC/MS
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烷基苯分子结构与分配系数间定量关系的研究 被引量:2
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作者 梁云霄 胡秀华 《齐齐哈尔轻工业学院学报》 1997年第3期36-38,共3页
应用Benson基团加和法,对烷基苯分子结构与分配系数间的关系进行了研究。对部分烷基苯的正辛醇/水分配系数做了估算,估算结果表明烷基苯分配系数的对数值具有良好的基团加和性,预测值与测量值吻合很好。
关键词 基团加和法 分配系数 烷基 烷基苯分子结构
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锆离子改善十烷基磷酸组装膜结构及性能研究 被引量:1
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作者 王天德 王荣 +2 位作者 吴霞琴 郭志钢 季魏魏 《电化学》 CAS CSCD 北大核心 2008年第2期175-179,共5页
利用烷基磷酸、金属锆离子和不锈钢电极表面的相互作用,通过表面自组装,在304不锈钢电极表面分别修饰了单层和双层烷基磷酸自组装膜,采用接触角和极化曲线对修饰电极进行测量.实验表明,双层烷基磷酸修饰膜具有更佳的耐腐蚀性能.
关键词 锆离子改善十烷基磷酸组装膜结构及性能研究
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HPLC法测定奥美沙坦酯2个氯代基因毒杂质的含量
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作者 马继红 郭廷富 +2 位作者 张曦 陈妍 袁清芳 《中文科技期刊数据库(引文版)医药卫生》 2024年第5期0073-0076,共4页
是为了建立HPLC 法测定奥美沙坦酯原料药中3和氯代基遗传毒杂质的含量。方法 色谱柱为苯基键合硅烷硅胶为填充剂(Kromail Eternity 5-Pheny Hexyl 250×4.6mm,5μm),用磷酸二氢钾溶液(将2.04克的磷酸二氢钾溶于水中,稀释到1000ml,... 是为了建立HPLC 法测定奥美沙坦酯原料药中3和氯代基遗传毒杂质的含量。方法 色谱柱为苯基键合硅烷硅胶为填充剂(Kromail Eternity 5-Pheny Hexyl 250×4.6mm,5μm),用磷酸二氢钾溶液(将2.04克的磷酸二氢钾溶于水中,稀释到1000ml,用磷酸将 pH调整到3.2)作为移动相,用乙腈作为移动相 B,用直线梯度法将其从样品中分离出来;该方法的探测波长为215 nm;流量1.0ml/分钟,温度40℃,10μ L进样。结果 结果表明,在0.17μ g/ml—8.5μ g/ml范围之内,3个样品的峰面积与其含量有很好的相关性(r=0.9999),平均加标为98.9%;结果表明,在0.17μ g/ml—8.5μ g/ml范围之内,杂质4与其峰面积之间有很好的相关性(r=0.9999),平均回收率为103.3%;杂质5质量浓度在0.17μg/ml~8.5μg/ml内与峰面积呈良好的线性关系(r=0.9998),平均回收率为97.7%。结论 本方法可用于同时测定奥美沙坦酯原料药中3和氯代基遗传毒杂质的含量,且专属性强,耐用性好。 展开更多
关键词 药物分析 杂质检测 高效液相色谱法 奥美沙坦酯 氯代烷基结构类杂质 潜在遗传毒杂质
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奥美沙坦酯中4-氯甲基-5-甲基-1,3-二氧杂环戊烯-2-酮和4,5-二氯甲基-1,3-二氧杂环戊烯-2-酮的HPLC法测定
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作者 袁抢云 陈程 +3 位作者 王鹏光 李海波 林玉琴 刘占红 《中国药品标准》 CAS 2018年第1期49-53,共5页
目的:建立高效液相色谱法(HPLC)测定奥美沙坦酯中氯代烷基结构类潜在基因毒性杂质[4-氯甲基-5-甲基-1,3-二氧杂环戊烯-2-酮(杂质1)和4,5二氯甲基-1,3-二氧杂环戊烯-2-酮(杂质2)]。方法:采用色谱柱为Kromasil Eternity 5-Phenyl Hexyl柱(... 目的:建立高效液相色谱法(HPLC)测定奥美沙坦酯中氯代烷基结构类潜在基因毒性杂质[4-氯甲基-5-甲基-1,3-二氧杂环戊烯-2-酮(杂质1)和4,5二氯甲基-1,3-二氧杂环戊烯-2-酮(杂质2)]。方法:采用色谱柱为Kromasil Eternity 5-Phenyl Hexyl柱(4.6 mm×250 mm,5μm);检测波长:215 nm,流动相A:乙腈:2.04 g·L^(-1)磷酸二氢钾溶液(用1.73 g·L^(-1)磷酸溶液调节pH值至3.4)(20∶80);流动相B:2.04 g·L^(-1)磷酸二氢钾溶液(用1.73 g·L^(-1)磷酸溶液调节p H值至3.4):乙腈(20∶80),进行梯度洗脱,流速为1.0 m L·min^(-1),柱温40℃,进样量10μL。结果:杂质1和杂质2与主峰分离良好,在浓度为0.106 6~0.710 4μg·m L^(-1)和0.123 5~0.617 4μg·m L^(-1)范围内杂质1和杂质2的线性关系良好(相关系数分别为1.000 0和0.997 1);杂质1和杂质2的平均回收率分别为98.09%和114.85%,RSD(n=9)分别为7%和7%。通过上述色谱条件进行验证,杂质1和杂质2检测限的相对浓度分别可达0.000 3%和0.000 4%,适用于杂质1和杂质2的测定。同时3批奥美沙坦酯成品中,杂质1和杂质2未检出,表明这两种杂质经过奥美沙坦酯的合成、精制和干燥处理后未传递到成品中。结论:经方法学验证,本法准确性好、灵敏度高,适用于奥美沙坦酯中的杂质1和杂质2的定量控制。 展开更多
关键词 高效液相色谱 奥美沙坦酯 氯代烷基结构类杂质 潜在基因毒性杂质
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Synthesis and Characterization of Tris(cyclopentylcyclopentadienyl)lanthanide Complexes (C_5H_9C_5H_4)_3NdBrLi(THF)_3 and (C_5H_9C_5H_4)_3SmTHF
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作者 崔冬梅 程建华中国科学院长春应化所高分子物理与化学国家重点实验室 +5 位作者 庄秀丽中国科学院长春应化所高分子物理与化学国家重点实验室 胡宁海中国科学院长春应化所高分子物理与化学国家重点实验室 金玑珠 陈文启 唐涛 黄葆同 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第1期78-82,共5页
(C5H9C5H4)(3)NdBrLi(THF)(4)(1)(C5H9=cyclopentyl) was obtained from the reaction of NdCl3 with C5H9C5H4Na and LiBr (Nd:Na:Li=1:2:1 molar ratio) in THE X-ray crystallography showed that the ten-coordinated neodymium ato... (C5H9C5H4)(3)NdBrLi(THF)(4)(1)(C5H9=cyclopentyl) was obtained from the reaction of NdCl3 with C5H9C5H4Na and LiBr (Nd:Na:Li=1:2:1 molar ratio) in THE X-ray crystallography showed that the ten-coordinated neodymium atom is bonded to three cyclopentylcyclopentadienyl(eta(5)) rings and a single bromine atom bridging a lithium which is bonded to three THF molecules. Complex 1 is triclinic, P1 space group with unit dimensions of a= 12.048(2), b= 13.498(3), c= 13.831(3)Angstrom, a = 104.16(3), beta = 104.07(3), gamma =95.96(3)degrees, V=2083.3(7)Angstrom(3), Z=2, D-c=1.35Mg/m(3) and F(000)=874. (C5H9C5H4)(3)SmTHF (2) was synthesized by reaction of anhydrous SmCl3 with C5H9C5H4Na at a molar ratio of 1:3. The structure was determined by X-ray crystallography. The ten-coordinated samarium atom is bonded to three cycloperrtylcyclopentadienyl rings and one oxygen of THF molecule to form a pseudo-tetrahedron. Complex 2 is orthorhombic, Fdd2 space group with unit cell dimensions of a =28.175(5)Angstrom, b =46.24(2) Angstrom, c =9.167(4) Angstrom(3), V=11943(8)Angstrom(3), Z= 16, D-c = 1.38Mg/m(3) and F(000)=5136. 展开更多
关键词 cyclopentylcyclopentadiene rare earth complex ND SM CRYSTALSTRUCTURE
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An alternate aqueous phase synthesis of the Pt3Co/C catalyst towards efficient oxygen reduction reaction 被引量:2
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作者 Jinjing Huang Chen Ding +2 位作者 Yongqiang Yang Gang Liu Wen-Bin Cai 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第12期1895-1903,共9页
Carbon supported Pt-Co alloys are among the most promising electrocatalysts towards oxygen reduction reaction(ORR)for the application in low temperature fuel cells and beyond,thus their facile and green synthesis is h... Carbon supported Pt-Co alloys are among the most promising electrocatalysts towards oxygen reduction reaction(ORR)for the application in low temperature fuel cells and beyond,thus their facile and green synthesis is highly demanded.Herein we initially report an alternate aqueous phase one-pot synthesis of such catalysts(containing nominally ca.20 wt.%Pt)based on dimethylamine borane(DMAB)reduction.The as-obtained electrocatalyst(denoted as Pt3Co/C-DMAB)is compared with the ones obtained by NaBH4 and N2H4·H2O reduction(denoted as Pt3Co/C-NaBH4 and Pt3Co/C-N2H4·H2O,respectively)as well as a commercial Pt/C,in terms of the structure and electrocatalytic property.It turns out that Pt3Co/C-DMAB exhibits the highest ORR performance among all the tested samples in an O2-saturated 0.1 mol/L HClO4,with the mass activity(specific activity)ca.4(6)times as large as that for Pt/C.After 10000 cycles of the accelerated degradation test,the half-wave potential for ORR on Pt3Co/C-DMAB decreases only by 4 mV,in contrast to 24 mV for that on Pt/C.Pt3Co/C-NaBH4 or Pt3Co/C-N2H4·H2O shows a specific activity comparable to that for Pt3Co/C-DMAB,but a mass activity similar to that for Pt/C.ICP-AES,TEM,XRD and XPS characterizations indicate that Pt3Co nanoparticles are well-dispersed and alloyed with a mean particle size of ca.3.4±0.4 nm,contributing to the prominent electrocatalytic performance of Pt3Co/C-DMAB.This simple aqueous synthetic route may provide an alternate opportunity for developing efficient practical electrocatalysts for ORR. 展开更多
关键词 ORR electrocatalyst Pt–Co alloy Aqueous phase synthesis Dimethylamine borane Structure and property
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Synthesis,Characterization and Crystal Structure of the Dimeric Organotin Compound:{[n-Bu_(2)Sn(O_(2)CCH_(2)CS_(2)NC_(4)H_(8))]_(2)O}_(2) 被引量:1
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作者 YIN Han-Dong XUE Sheng-Cai WANG Qi-Bao 《无机化学学报》 SCIE CAS CSCD 北大核心 2004年第4期421-425,共5页
The title compound,{[n-Bu_(2)Sn(O_(2)CCH_(2)CS_(2)NC_(4)H_(8))]_(2)O}_(2),has been synthesized by the reaction of(tetrahydro-pyrrodithiolocarbamoylthio)acetic acid with the di-n-bubyltin oxide in1∶1molar ratio.The co... The title compound,{[n-Bu_(2)Sn(O_(2)CCH_(2)CS_(2)NC_(4)H_(8))]_(2)O}_(2),has been synthesized by the reaction of(tetrahydro-pyrrodithiolocarbamoylthio)acetic acid with the di-n-bubyltin oxide in1∶1molar ratio.The complex has been characterized by elemental analysis,IR and NMR.The crystal structure of it has been determined by X-ray single crystal diffraction.And the results showed that the crystal belongs to triclinic system with space group P1and some crystal parameters:a=1.2202(9)nm,b=1.3158(10)nm,c=1.3804(10)nm,α=111.215(9)°,β=99.357(9)°,γ=96.075(10)°,V=2.006(2)nm 3,Z=1,F(000)=908,μ=1.489mm^(-1),D c=1.474g·cm^(-3),R_(1)=0.0375,wR_(2)=0.0839.The complex has a centrosymmetric dimer structure mode with a four-membered central endo-cyclic Sn_(2)O_(2)unit in which two bridged oxygen atoms both connect with an exo-cyclic tin atom which has a distorted octahedron.Each of the endo-cyclic tin atoms exhibits a distorted trigonal bipyramid coordination geometry with an additional weak coordination carboxylate oxygen.Four carboxylate ligands are divided into two types.And two of them are bidentate and connecting to each of exo-cyclic tin atoms by using both oxygen atoms,whereas the others bridge to each pair of exo-and endo-cyclic tin atoms utilizing one oxygen atom only.CCDC:220513. 展开更多
关键词 organotin complex (tetrahydropyrrodithiolocarbamoylthio)acetic acid systhesis crystal structure
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Syntheses and Crystal Structures of 4,4′Diformyl-diphenoxyethane and 4,4′4′′-Triformyl-triphenoxytriethylamine 被引量:3
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作者 马震 刘世雄 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第5期533-537,共5页
Two title compounds, 4,4?diformyl-diphenoxyethane (compound 1, C16H14O4) and 4,4?4创-triformyl-triphenoxytriethylamine (compound 2, C27H27NO6), were synthesized by condensation of 4-hydroxybenzaldehyde with 1,2-dichlo... Two title compounds, 4,4?diformyl-diphenoxyethane (compound 1, C16H14O4) and 4,4?4创-triformyl-triphenoxytriethylamine (compound 2, C27H27NO6), were synthesized by condensation of 4-hydroxybenzaldehyde with 1,2-dichloroethane and tris(2-chloroethyl)amine, respectively in dimethyl formamide in the presence of anhydrous potassium carbonate. The crystal data are: monoclinic, P21/c, a = 7.571(2), b = 12.608(3), c = 7.357(2) ? b = 105.823(6)? V = 675.7(2) 3, Mr = 270.3, Z = 2, Dc = 1.328 g/cm3, F(000) = 284, m(MoKa) = 0.096 mm-1, R = 0.0537 and wR = 0.2189 for compound 1; and monoclinic, P21/n, a = 11.7162(6), b = 9.0042(6), c = 22.908(2) ? b = 99.505(1)? V = 2383.5(3) ?, Mr = 461.50, Z = 4, Dc = 1.286 g/cm3, F(000)= 976, m(MoKa) = 0.091 mm-1, R = 0.0464 and wR = 0.1462 for compound 2. The molecule of compound 1 (dialdehyde) is located at the crystallographic inversion center nearby the midpoint of C(8)C(8A) single bond. The three chains in the molecule of compound 2 (trialdehyde) are of non-crystallographic pseudo-C3 symmetry, and each of them is quite planar. 展开更多
关键词 crystal structure DIALDEHYDE trialdehyde
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CRYSTAL STRUCTURE OF RhCl(dppm)_2·H_2O 被引量:1
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作者 邵昌平 程国宝 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1993年第5期343-345,共3页
C50H46OP4ClRh, RhCl(dppm)2 · H2O, Mr = 922. 2, monoclinic, P21/2, a=10. 532(3), b=22.574(8), c=18. 641(8) A, β=93. 41(3)°, V = 4424 (3) A3, Z = 4, Dc=1. 386 g. cm-3, λ(MoKα) = 0. 71073A , F(000) = 1904. T... C50H46OP4ClRh, RhCl(dppm)2 · H2O, Mr = 922. 2, monoclinic, P21/2, a=10. 532(3), b=22.574(8), c=18. 641(8) A, β=93. 41(3)°, V = 4424 (3) A3, Z = 4, Dc=1. 386 g. cm-3, λ(MoKα) = 0. 71073A , F(000) = 1904. The structure was determined by direct methods and difference Fourier syntheses and refined by full-matrix least-squares to final R = 0. 037 and Rw = 0. 036 for 3432 (F> 6. 0σ(F) ) observed reflections. The structure of the title compound contains RhCl-(dppm)2 and non-coordinated H2O molecules. The rhodium atom is coordinated by one chlorine atom and four phosphorus atoms of two DPPM ligands forming a tetragonal pyramidal configuration. 展开更多
关键词 crystal structure Rh-Cl-DPPE complex
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Synthesis and Characterization of Linked Clusters Capped by Alkylidyne
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作者 ZHANG Yu-Hua CHI Wei-Guang +2 位作者 YIN Yuan-Qi HUANG Zi-Xiang WU Qiang-Jin 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第1期17-21,共5页
The lsolobal displacement reaction between the dianion {M(CO)3[(h5-C5H4) C(O)C6H4C(O)(h5-C5H4)](CO)3M}2- and two molecules of [(m3-C)CO2Et]Co3(CO)9 gave rise to the formation of terephthaloyl(biscyclopentadienyl)-brid... The lsolobal displacement reaction between the dianion {M(CO)3[(h5-C5H4) C(O)C6H4C(O)(h5-C5H4)](CO)3M}2- and two molecules of [(m3-C)CO2Et]Co3(CO)9 gave rise to the formation of terephthaloyl(biscyclopentadienyl)-bridged double cluster complexes [(h5-C5H4)C(O)C6H4C(O)(h5-C5H4)]{[(m3-C)CO2Et]Co2M(CO)8}2 (M = Mo 1, M = W, 2). In the reaction, single cluster complexes[(m3-C)CO2Et]-Co2M(CO)8[h5-C5H4C(O)C6H4CO2CH3] ( M = Mo 3, M = W, 4) were yielded as by-products. All the cluster complexes were characterized by C/H analysis, IR and 1H NMR spectroscopy, and the structure of 3 has been determined by single-crystal X-ray diffraction method. Crystal data: Mr = 750.19, monoclinic, space group P21/c, a = 22.652(5), b = 8.954 (2), c = 14.530(3) ? b = 104.00(3), V = 2859.6(10) 懦, Z = 4, Dc = 1.743 mg/m? F(000) = 1488, m = 1.644 mm-1, the final R = 0.0555 and wR = 0.1353 for 5519 observations with I > 2s(I). 展开更多
关键词 transition metal linked cluster crystal structure COBALT
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Synthesis and Crystal Structure of N-(5-Phenylseleno)pentyl Succinimide
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作者 张万轩 于海涛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第5期517-519,共3页
N-(5-phenylseleno)pentyl succinimide 1, C15H19NO2Se (Mr = 324.27), was prepared by treating Br(CH2)5SePh with potassium succinimide. Its crystal structure has been determined by X-ray single-crystal diffraction. The c... N-(5-phenylseleno)pentyl succinimide 1, C15H19NO2Se (Mr = 324.27), was prepared by treating Br(CH2)5SePh with potassium succinimide. Its crystal structure has been determined by X-ray single-crystal diffraction. The crystal of 1 belongs to monoclinic system, space group P21/c with the crystal cell parameters: a = 18.018(6), b = 5.980(2), c = 14.682(5) ? = 109.977(6)? V = 1486.7(9) 3, Z = 4, Dc = 1.449 g/cm3, (MoK? = 2.523 mm-1, F(000) = 664,the final R = 0.0302 and wR = 0.0666 for 2623 independent observed reflections with I > 2(I). Structure analyses revealed that there exist strong nonclassical hydrogen bonds (CH…O). 展开更多
关键词 N-(5-phenylseleno)pentyl succinimide PREPARATION crystal structure
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Structural Analysis of Hydroxamate Reagents by X-Ray Diffraction 被引量:1
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作者 Ratan Chowdhury Frank Antolasic 《Journal of Earth Science and Engineering》 2012年第10期584-589,共6页
Axis House manufactures and supplies alkyl hydroxamate reagent of various carbon chain lengths for application in flotation of oxide copper and other minerals. As a part of reagent performance improvement, the structu... Axis House manufactures and supplies alkyl hydroxamate reagent of various carbon chain lengths for application in flotation of oxide copper and other minerals. As a part of reagent performance improvement, the structural factors of hydroxamate are examined by various analytical tools in particular with X-ray diffraction of single crystals. In a recent publication, the structures of n-octyl hydroxamic acid and its corresponding potassium salt are presented with findings of hydroxamic functional group geometric preference, H-bonding, keto-enol tautomerisation, acid-salt aggregation and alignment of carbon chain. In this paper, an example of branched alkyl hydroxamate3,5,5-trimethyl hexyl hydroxamate. hydroxamate is presented and compared with the result of linear alkyl 展开更多
关键词 Alkyl hydroxamic acid potassium alkyl hydroxamate X-ray crystal structures flotation of oxide copper minerals.
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Study on the effect of methyl bromide and metham sodium fumigation on the soil protozoan community in a greenhouse environment
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作者 CAO Zhi-ping HAN Xue-mei +3 位作者 Yosef Steinberger YANG Hang CHEN Yun-feng PENG Li-de 《Journal of Environmental Science and Engineering》 2008年第10期30-40,共11页
We examined soil fumigation effects on soil protozoan abundance and community structure in greenhouses and explored the capacity of protozoa to recover after disturbances. A randomized complete block design with five ... We examined soil fumigation effects on soil protozoan abundance and community structure in greenhouses and explored the capacity of protozoa to recover after disturbances. A randomized complete block design with five treatments and 4 replicates was set up in Qingzhou, Shandong Province, China. In addition to methyl bromide (MB) and untreated control (CK), three alternative fumigation treatments were studied, including MB+VIF (virtually impermeable films), metham sodium (MS) and MS+VIF. Tomato cultivars (Lyeopersicum eseulentum Mill), cv. Maofen-802 were selected as test crops. Results of four fumigations were demonstrated through three-level ten-fold dilution methodology. Abundance of three groups of soil protozoa-flagellates, amoebae, and ciliates was measured from July 2002 to July 2003. Results indicated that two chemical fumigants and their combinations with physical material all significantly repressed soil protozoan abundance. MB was a stronger fumigant than MS, and use of VIF increased their repressive power. The most serious population reduction occurred in amoebae, thus, they also required the longest time to recover. MB and MS also changed the protozoan community structure. MB use decreased the percentage of amoebae but increased percentage of ciliates, while MS incrcased the percentagc of amoebae and decreased the percentage of flagellates in the protozoan community. 展开更多
关键词 AMOEBAE CILIATES FLAGELLATES metham sodium methyl bromide
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Structural properties of hydroxyl-substituted alkyl benzenesulfonates at the water/vapor and water/decane interfaces 被引量:1
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作者 SUN HuanQuan XIAO HongYan LIU XinHou 《Science China Chemistry》 SCIE EI CAS 2011年第7期1078-1085,共8页
Molecular dynamics simulations have been performed to investigate the structural properties of hydroxyl-substituted alkyl benzenesulfonate monolayers formed at the water/vapor and water/decane interfaces.We report a d... Molecular dynamics simulations have been performed to investigate the structural properties of hydroxyl-substituted alkyl benzenesulfonate monolayers formed at the water/vapor and water/decane interfaces.We report a detailed study of the interfacial properties-liquid density profile,hydrogen bond structure,surfactant aggregate structure and order parameter-of the novel anionic surfactant,sodium 2-hydroxy-3-decyl-5-octylbenzenesulfonate(C10C8OHphSO3Na).Simulation results show that:with increasing number of surfactant molecules,the average number of intramolecular hydrogen bonds per surfactant molecule in the monolayer decreases,but the structures forming the intramolecular hydrogen bonds still play a dominant role;the hydrophobic part of the alkyl tail chain,especially the decyl substituent on the third carbon atom in the benzene ring,becomes straighter,and more ordered towards the external interface at higher surfactant coverage;two-dimensional radial distribution functions can describe the characteristic of surfactant aggregate structures and highlight the decane phase effect on the orientation of the hydrophobic part of the surfactant;the surfactant molecules readily form long-range hydrogen bonded structures.Our results are an important complement to experimental studies.We used the all-atom model by employing the GROMACS and ffAMBER programs in the simulations,which provides a new way to simulate the interfacial behavior of alkyl benzenesulfonate surfactants. 展开更多
关键词 molecular dynamics hydroxyl-substituted alkyl benzenesulfonates hydrogen bond radial distribution function order parameter
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Layered double hydroxides with larger interlayer distance for enhanced pseudocapacitance 被引量:6
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作者 肖元化 苏当成 +4 位作者 王雪兆 吴诗德 周立明 方少明 李峰 《Science China Materials》 SCIE EI CSCD 2018年第2期263-272,共10页
The interlayer space of the layered materials is not always the electrochemical active area for contributing to the pseudocapacitive process. To our knowledge, few efforts have been devoted to investigating the effect... The interlayer space of the layered materials is not always the electrochemical active area for contributing to the pseudocapacitive process. To our knowledge, few efforts have been devoted to investigating the effect of interlayer distance of layered double hydroxides(LDHs) on pseudocapacitors. Here, we obtained the CoAl-LDH with different interlayer distance via the reaction in aqueous media hydrothermally. Electrochemical characterization reveals that the CoAl(DS^-(dodecyl sulfate))-LDHs with an interlayer distance of 2.58 nm can deliver higher specific capacitance of 1481.7 F g^-1 than CoAl(SO4^2-)-LDH(0.87 nm, 1252.7 F g^-1) and CoAl(CO3^2-)-LDH(0.76 nm, 1149.2 Fg^-1) at a discharge current density of 1 A g^-1. An asymmetric supercapacitor with the CoAl(DS^-)-LDHs‖activated carbon also shows a better electrochemical performance, including a high energy density of54.2 W h kg^-1 at a power density of 0.9 kW kg^-1 and a longterm stability, in comparison with CoAl(SO4^2-)-LDH and CoAl(CO3^2-)-LDH ‖activated carbon. 展开更多
关键词 layered double hydroxides interlayer distance HYDROTHERMAL asymmetric supercapacitors
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Unusual reaction of a tungsten alkylidyne complex with water.Formation,characterization,and crystal structures of oxo trimers
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作者 DOUGAN Brenda A. 《Science China Chemistry》 SCIE EI CAS 2011年第12期1903-1908,共6页
The reaction of the alkyl alkylidyne W(CH2CMe3)3(=CSiMe3) (1) with H20 in THF and with D20 in benzene-d6 gave two new trimeric oxo complexes: W3O3(μ=O)3(CH2CMe3)6(THF)3 (2) and [W303(μ=O)3(Ch2CMe3... The reaction of the alkyl alkylidyne W(CH2CMe3)3(=CSiMe3) (1) with H20 in THF and with D20 in benzene-d6 gave two new trimeric oxo complexes: W3O3(μ=O)3(CH2CMe3)6(THF)3 (2) and [W303(μ=O)3(Ch2CMe3)6(D2O)3] 2benzene-d6 (3.2benzened6), respectively, each containing two alkyl ligands per W atom. This is in contrast to the dimer W2o(β-O)(CH2CMe3)6, containing three alkyl ligands per W atom, from the previously reported reaction of the alkyl alkylidyne analog W(CH2CMe3)3- (=-CCMe3) with H2O. In the reaction of 1 with D20 in THF, an unstable intermediate W2O2(μ-O)(CD2SiMe3)2(CH2CMe3)4 (4-d4) was identified. Kinetic studies of the reactions of 1 with excess H2O and D2O in THF-ds, yielding 4 and 4-d4, respectively, give a kinetic isotope effect (KIE) of 3.46(3) at 298(1) K, suggesting that the disappearance of 1 is a rate-determining step. 展开更多
关键词 alkylidyne WATER oxo complexes kinetic isotope effect
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