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Use of Ultrasound and Microwave Irradiation for Clean and Efficient Synthesis of 3,3’-(Arylmethylene)bis (2-hydroxynaphthalene-1,4-dione) Derivatives 被引量:2
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作者 Aldo S. de Oliveira Luana C. Llanes +2 位作者 Ricardo J. Nunes Rosendo A. Yunes Inês M. C. Brighente 《Green and Sustainable Chemistry》 2014年第4期177-184,共8页
Nine 3,3’-(arylmethylene)bis(2-hydroxynaphthalene-1,4-dione) derivatives were synthesized through the reaction between 2-hydroxy-1,4-naphthalen-1,4-dione and different aromatic alde-hydes in water applying ultrasonic... Nine 3,3’-(arylmethylene)bis(2-hydroxynaphthalene-1,4-dione) derivatives were synthesized through the reaction between 2-hydroxy-1,4-naphthalen-1,4-dione and different aromatic alde-hydes in water applying ultrasonic irradiation for 5 min at room temperature and microwave irradiation for 15 min at 70°;C. Two of the nine derivatives, compounds 3-e and 3-i, obtained from 3-bromo-hydroxybenzaldehyde and 5-methylfuran-2-carbaldehyde, respectively, are previously unpublished. The structures of all compounds were established on the basis of their spectral data and mass analysis. The attractive features of this synthesis protocol include mild conditions, high atom-economy and excellent yields with the elimination of water as the only by-product. 展开更多
关键词 2-hydroxy-1 4-naphthoquinone 3 3’-(Arylmethylene)bis(2-hydroxynaphthalene-1 4-dione) DERIVATIVES Green chemistry
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Analysis of Numerical Results in High Temperature Congealment and Chemistry Non-equilibrium Flow Field
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作者 Hong-tao Zheng Zhi-yong Tan +2 位作者 Hai-ou Sun Chun-liang Zhou Zhi-ming Li 《Journal of Marine Science and Application》 2002年第1期26-34,共9页
Using the air plasma ignition technique, physicochemical process of burning can be accelerated; concentration limit ofretrofires both can be extended; reliability of retrofires and stability of burning can be improved... Using the air plasma ignition technique, physicochemical process of burning can be accelerated; concentration limit ofretrofires both can be extended; reliability of retrofires and stability of burning can be improved. In this paper, using internalequivalent heat area in place of electric are that created Ohm heat, the flow fields of thermodynamic equilibrium chemistry con-gealment and chemistry non-equilibrium in the plasma generator were simulated. The influences of the inlet prerotation angleof air, the inlet total pressure of air and the airflow compression angle of spray nozzle on the temperature on the surface of elec- 展开更多
关键词 plasma GENERATOR chemistry non - EQUILIBRIUM IGNITION technique numerical calculation
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Preparation and spectroscopic, and thermal decomposition kinetic studies of europium(Ⅲ) complex [Eu(HNBD)_3] (HNBD: 1-(6-hydroxy-1-naphthyl)-1,3-butanedione)
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作者 WANG Dunjia ZHENG Chunyang SUN Tingquan 《Rare Metals》 SCIE EI CAS CSCD 2007年第4期335-341,共7页
The complex of Eu(IH) with 1-(6-hydroxy- 1-naphthyl)- 1,3-butanedione (HNBD) was prepared for the first time and characterized by elemental analysis, IR, UV, fluorescence spectrum, and DTA-TG-DTG techniques. The... The complex of Eu(IH) with 1-(6-hydroxy- 1-naphthyl)- 1,3-butanedione (HNBD) was prepared for the first time and characterized by elemental analysis, IR, UV, fluorescence spectrum, and DTA-TG-DTG techniques. The IR and UV-visible spectra showed that Eu(Ⅲ) ion was coordinated to the HNBD ligand. The fluorescence spectrum showed the presence of Eu^3+ characteristic emission. The TG-DTA-DTG curves showed that the thermal decomposition of the anhydrous complex was a two-stage process and the final residue was Eu2O3. The thermal decomposition kinetic parameters of the complex were evaluated from TG-DTG data by using three kinds of integral methods (Coat-Redfem equation, Horowitz and Metzger equation, Madhusudanan-Krishnan-Ninan equation). The kinetic parameters of the first stage are E^* = 164.02 kJ.moll, A = 1.31 × 10^15 s^-l, AS^*= 42.27 J·K^-l·mol^-l, △H^* = 159.51 kJ·mol^-l, △G^*= 136.54 kJ·mol^-l, and n = 3.1, those of the second stage are E^*= 128.52 kJ·mol^-l, A = 1.44× 106 s^-1, △S^*= - 136.89 J·K^-l·mol^-l, △H^* = 120.41 kJ·mol^-l, △G^*= 283.85 kJ·mol^-l, and n = 1.1. 展开更多
关键词 physical chemistry thermal decomposition kinetics spectroscopic studies Eu(Ⅲ) complex 1-(6-hydroxy-1-naphthyl)- 1 3-butanedione
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Hydro-Chemical Characterization of Glacial Melt Waters Draining from Langtang Valley, Nepal
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作者 Anisha Tuladhar Rijan Bhakta Kayastha +1 位作者 Smriti Gurung Ahuti Shrestha 《Journal of Water Resource and Protection》 2015年第8期605-613,共9页
A detailed analytical study of the physico-chemical parameters of melt water draining from glaciers of Langtang Valley with an elevation ranging from 1395 m a s l to 4200 m a s l in Rasuwa district, Nepal was carried ... A detailed analytical study of the physico-chemical parameters of melt water draining from glaciers of Langtang Valley with an elevation ranging from 1395 m a s l to 4200 m a s l in Rasuwa district, Nepal was carried out in order to study the seasonal and altitudinal variation in hydro-chemistry along the Langtang River and glacial melts from the Lirung and the Khimsung Glaciers. The study was carried out during 6 - 10 April and 30 June-3 July, 2014 at 11 sites. A total of 22 composite samples were collected. The concentration of cations and anions of the Langtang Valley were found in the order Ca2+ > K+ > Na+ > Mg2+ and , respectively. Significant seasonal variation in electrical conductivity (EC), turbidity, dissolved oxygen (DO), calcium (Ca), sodium (Na), magnesium (Mg), chloride (Cl), sulphate (SO4) and total phosphorus (TP-PO4) and altitudinal variation in EC, total dissolved solids (TDS), DO and Na was found out. The concentrations of the heavy metals (As, Al, Mn, Zn, Cd, Cr) were below the detection limit except Fe (0.5 to 18.1 mg/l), which was highly variable. Calcium carbonate weathering was found out to be the major source of dissolved ions in the region. The elemental ratios (Ca/Si and K/Na) were typical of glacial melt water and the low Na/Cl and K/Cl ratios indicated major contribution from atmospheric precipitation to the observed dissolved ions of melt waters. The study showed an increase in the concentration of cations as compared to previous studies, which could be attributed to increasing weathering rates due to temperature increase. Elevated concentration of NO3 and TP-PO4 compared to previous studies show the effect of human impact in the region. Differences in the melt water composition between the debris covered and clean type glacier was found out. 展开更多
关键词 hydro-chemistry Langtang River WEATHERING Process GLACIER MELT Water
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Information Environmental sciences update referneces in Chinese journals——Selected from Acta Scientiae Circumstantiae,ISSN 0253-2468;Environental Chemistry,ISSN0254-6108;Acta Ecologica Sinica,ISSN 100-0933
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《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1993年第2期241-243,共3页
关键词 ISSN Information Environmental sciences update referneces in Chinese journals Selected from Acta Scientiae Circumstantiae ISSN 0253-2468 Environental chemistry ISSN0254-6108 Acta Ecologica Sinica ISSN 100-0933
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化学场对膨润土水-力特性影响研究进展 被引量:15
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作者 陈永贵 黄润秋 +1 位作者 朱春明 叶为民 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2014年第3期398-405,共8页
在阐述处置库近场化学环境的基础上从化学场对膨润土的膨胀力影响、渗透性影响、体变特性影响及模型研究4个方面回顾和总结了国内外的研究进展,通过分析影响因素、作用机理以及研究中存在的问题指出当前研究中的不足,并提出进一步研究... 在阐述处置库近场化学环境的基础上从化学场对膨润土的膨胀力影响、渗透性影响、体变特性影响及模型研究4个方面回顾和总结了国内外的研究进展,通过分析影响因素、作用机理以及研究中存在的问题指出当前研究中的不足,并提出进一步研究的建议. 展开更多
关键词 处置库 化学场 缓冲 回填材料 高压实膨润土 -力学性能
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1-苄基-4-苯基-1H-1,2,3-三唑的合成
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作者 彭艳芬 刘天宝 汪新 《科技创新导报》 2011年第31期141-142,共2页
利用卞溴和叠氮化钠在DMF中反应合成了叠氮卞,进而与苯乙炔进行Click反应,成功地合成了1-苄基-4-苯基-1H-1,2,3-三唑,产率达到了98%,并通过红外光谱及核磁共振光谱对其结构进行了表征。
关键词 1 2 3-三唑 CLICK chemistry 叠氮化物
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2022年汉江流域中游“汛期反枯”背景下的区域地下水化学特征
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作者 张奥奇 杨文兵 +2 位作者 何贞竹 付文进 苏召帝 《地下水》 2024年第2期26-30,共5页
2022年6月份,长江流域由于大气环流异常等因素而爆发大面积的严重干旱,产生了“汛期反枯”的异常现象,这种现象一直持续到当年冬季。汉江是长江第一大支流,选取汉江中游襄阳段岸线带周边地下水为研究对象开展研究,采用多元统计分析、Pi... 2022年6月份,长江流域由于大气环流异常等因素而爆发大面积的严重干旱,产生了“汛期反枯”的异常现象,这种现象一直持续到当年冬季。汉江是长江第一大支流,选取汉江中游襄阳段岸线带周边地下水为研究对象开展研究,采用多元统计分析、Piper三线图、主成分分析、Gibbs图等方法对该地区地下水水化学特征及动态变化进行分析。结果表明:研究区地下水水化学类型主要为低矿化度偏碱性水,地下水组分中的阳离子以Ca^(2+)和Na^(+)为主,阴离子以HCO_(3)^(-)为主,9月地下水pH偏高,地下水咸度有所下降;6月汉江流域襄阳段周边的地下水类型主要为HCO_(3)·SO_(4)-Ca·Mg型,9月地下水存在向HCO_(3)-Na型转化的趋势,离子浓度变化大多是整体变化,可能与周边含水层的侧向补给有关;地下水水化学特征受到周边碳酸盐岩和硅酸盐岩风化溶解共同控制,靠近下游区域的地下水阳离子交替吸附作用较强,受到干旱少雨的影响,导致该区域阳离子吸附作用明显减弱。 展开更多
关键词 汉江中游 汛期反枯 地下水 水化学特征 因子分析
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西山煤田构造-水文地质对煤层气成藏的控制作用 被引量:8
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作者 曾玲 孙晓光 +1 位作者 崔少华 眭晋阳 《煤炭科学技术》 CAS CSCD 北大核心 2019年第9期80-88,共9页
煤层气富集成藏受构造、沉积环境、水文地质条件、岩浆活动等多方面因素控制,为了研究西山煤田煤层气富集的主控因素及其成藏规律,通过资料收集整理、采样分析研究,发现西山煤田煤层气成藏的主控因素为构造及水文地质条件。利用多口西... 煤层气富集成藏受构造、沉积环境、水文地质条件、岩浆活动等多方面因素控制,为了研究西山煤田煤层气富集的主控因素及其成藏规律,通过资料收集整理、采样分析研究,发现西山煤田煤层气成藏的主控因素为构造及水文地质条件。利用多口西山煤田水文孔的资料,分别对太原组含水层及山西组含水层的水动力场和水化学场进行研究;利用煤层气井的含气量等资料,找出对煤层气有利的构造、水动力、水化学因素,提出3种构造-水动力成藏模式;最后基于前面的研究提出构造-水动力控制下的煤层气富集区识别标准,对研究区进行富集区识别。研究表明:①西山煤田煤系地层水动力场可以分为三部分地下水流动系统:西北部系统Ⅰ、中南部系统Ⅱ和东部系统Ⅲ;其中屯兰矿东曲矿南部、原相地区以及西部水峪贯向斜核部、杜儿坪断层附近,水动力活动相对较弱,有利于煤层气成藏;②有利于煤层气富集的水化学类型为重碳酸钠型;③提出构造-水动力作用有利于煤层气聚集成藏的3种模式:单斜-水动力成藏、向斜-水动力成藏、断层-水动力成藏;④对西山煤田进行煤层气富集区识别,识别出邢家社附近和杜儿坪南部2个富集区。用上述方法将构造-水文地质条件对煤层气成藏的控制作用定量化和标准化,有利于其他区块参考和利用。 展开更多
关键词 构造 水动力 水化学 西山煤田 成藏模式
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Dynamical variations in groundwater chemistry influenced by intermittent water delivery at the lower reaches of the Tarim River 被引量:3
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作者 CHENYongjin CHENYaning +3 位作者 LIUJiazhen LIWeihong IJun XUChangchun 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期13-19,共7页
The water of Bosten Lake was released to lower reaches of the Tarim River for 5 times from 2000 to 2002. The changes of total dissolved solid (TDS) and the major ions (SO2-4, Cl-, Na+, Ca2+, Mg2+ and HCO-3) were ana... The water of Bosten Lake was released to lower reaches of the Tarim River for 5 times from 2000 to 2002. The changes of total dissolved solid (TDS) and the major ions (SO2-4, Cl-, Na+, Ca2+, Mg2+ and HCO-3) were analyzed during this period. It was found out that TDS and the concentrations of the major ions initially and quickly increased and then decreased, but finally increased again. These changes were different at different distances from the river, which indicated that the groundwater changes relied on the distance from the river. In addition, the salt in groundwater was only diluted but not removed by the water. It was suggested that ecological measures should be sought to really promote the quality of the groundwater at the lower reaches of the Tarim River. 展开更多
关键词 water delivery groundwater chemistry hydro-salinity movement the Tarim River
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Ni-Fe/C催化剂制备及其催化苯酐选择性加氢制苯酞
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作者 顾运江 王维 +2 位作者 李振斌 魏作君 刘迎新 《工业催化》 CAS 2014年第10期761-764,共4页
以NaBH4对疏水活性炭进行处理,采用等体积浸渍法制备疏水活性炭负载掺杂助剂Fe的Ni基催化剂,用于苯酐液相选择性加氢制苯酞,考察Ni含量和活性炭处理对催化剂性能的影响。结果表明,疏水活性炭经NaBH4处理后制备的15%Ni-Fe/C催化剂对苯酐... 以NaBH4对疏水活性炭进行处理,采用等体积浸渍法制备疏水活性炭负载掺杂助剂Fe的Ni基催化剂,用于苯酐液相选择性加氢制苯酞,考察Ni含量和活性炭处理对催化剂性能的影响。结果表明,疏水活性炭经NaBH4处理后制备的15%Ni-Fe/C催化剂对苯酐加氢表现出很好的催化性能,在180℃、4.0 MPa、苯酐5.0 g、催化剂用量以Ni占原料质量的1%计和甲苯50 mL条件下,苯酐转化率为100%,苯酞选择性为95.2%,催化剂重复使用5次,仍保持很好的活性和选择性。 展开更多
关键词 催化化学 Ni-Fe催化剂 活性炭 苯酐 选择性加氢 苯酞
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Syntheses and Crystal Structures of Two New Supramolecular Architectures Constructed from the Main Group Metal Chloride and Protonated 2-(3-Pyridyl)benzimidazole 被引量:1
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作者 夏昌坤 吴小园 +1 位作者 吴鼎铭 卢灿忠 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第3期318-323,共6页
The reactions of SbCl3 and HgCl2 with 2-(3-pyridyl)benzimidazole (PyBIm) in solution acidified with HCl have been investigated. The PyBIm ligands are protonated into 2-(3-pyridinio)benzimidazolium (H2PyBIm) ca... The reactions of SbCl3 and HgCl2 with 2-(3-pyridyl)benzimidazole (PyBIm) in solution acidified with HCl have been investigated. The PyBIm ligands are protonated into 2-(3-pyridinio)benzimidazolium (H2PyBIm) cations and the corresponding metal ions are bonded with chloride atoms into coordination anions, forming two new coordination compounds, namely, (H2PyBIm)(SbCl5) 1 and (H2PyBIm)2(Hg2Cl8) 2. Both compounds were characterized by X-ray crystallography. Crystal data for 1: triclinic, space group P1^- with a = 5.7030(7), b = 9.0625(11), c = 16.5929(18) A, α = 91.808(7)°, β = 93.234(6), γ = 99.216(7)°, C12H11N3SbCl5, Mr = 496.24, V = 844.44(17) A^3, Z = 2, Dc = 1.952 g/cm^3, μ(MoKα) = 2.419 mm^-1, F(000) = 480, the final R = 0.0496 and wR = 0.1382 for 3433 observed reflections (I 〉 2σ(I)). Crystal data for 2: monoclinic, space group P21/c with a = 7.8061(5), b = 15.8127(9), c = 12.2435(9) , β = 91.955(4)o, C24H22N6Hg2Cl8, Mr = 1079.26, V = 1510.40(17) 3, Z = 2, Dc = 2.373 g/cm3, μ(MoKα) = 10.889 mm-1, F(000) = 1008, the final R = 0.0293 and wR = 0.0562 for 2854 observed reflections (I 〉 2σ(I)). X-ray diffraction analysis reveals that the antimony(III) is five-coordinated, exhibiting a slightly distorted square-pyramidal coordination geometry; while in 2, a dimeric [Hg2Cl8]^4-anion consists of two trigonal bipyramids sharing two common edges. The organic cations and coordination anions are connected into a one-dimensional belt and a two-dimensional sheet through N-H···Cl hydrogen bonding interactions in compounds 1 and 2, respectively; both are further aggregated into 3D frameworks by strong π-π contacts. 展开更多
关键词 crystal engineering hydrogen bonding interactions supramolecular chemistry 2-(3-pyridy1)benzimidazole antimony compound mercury compound
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Ce_xTi_(1-x)O_2 Mixed Oxides Supported CuO Catalyst for NO Reduction by CO 被引量:1
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作者 楼莉萍 蒋晓原 +3 位作者 陈英旭 吕光烈 周仁贤 郑小明 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第3期331-336,共6页
Ce x Ti 1- x O 2 mixed oxides of different mole ratios ( x =0, 0.1, 0.2~0.9, 1.0) were prepared by co precipitation of TiCl 4 with Ce(NO 3) 3 and then loaded with different amounts of CuO. The effe... Ce x Ti 1- x O 2 mixed oxides of different mole ratios ( x =0, 0.1, 0.2~0.9, 1.0) were prepared by co precipitation of TiCl 4 with Ce(NO 3) 3 and then loaded with different amounts of CuO. The effects of CuO on NO+CO reaction were investigated, and the structure and reductive properties of various CuO/Ce x Ti 1- x O 2 were characterized by the methodologies of BET, TPR and XRD. The results show that different Ce/Ti mole ratios and calcination temperatures induce changes of structure and reductive properties of the Ce x Ti 1- x O 2 mixed oxides. When x =0.1~0.5, amorphous CeTi 2O 6 phase mainly forms at 650 ℃ compared to the formation of CeTi 2O 6 which crystallizes at 800 ℃. When x >0.6, some TiO 2 enters the CeO 2 lattice and a CeO 2 TiO 2 solid solution is formed. The activity of 6%CuO/Ce x Ti 1- x O 2 calcined at 650 ℃ is largely affected by the x values, which is the highest when x =0.3, 0.4 and 0.9. The NO conversion reaches 70% at a reaction temperature of 150 ℃. By comparison, the x values have little effect on the activity of 6%CuO/Ce x Ti 1- x O 2 calcined at 800 ℃ . There are strong interactions between CuO and CeTi 2O 6, i.e., formation of the CeTi 2O 6 phase shifts the CuO reduction peak temperature from 380 to 200 ℃, and CuO, in turn, shifts the CeTi 2O 6 reduction peak temperature from 600 to 300 ℃. 展开更多
关键词 catalitic chemistry Ce x Ti 1- x O 2 mixed oxides CuO/Ce x Ti 1- x O 2 catalysts CeTi 2O 6 phase NO+CO reaction activity rare earths
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Morphology and Thermal Behavior of Polypropylene/Easily Hydrodegraded Polyester Blend Fibers
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作者 李梅 付中玉 +1 位作者 张大省 王庆瑞 《Journal of China Textile University(English Edition)》 EI CAS 2000年第2期50-52,共3页
Ultrafine polypropylene fibers are prepared frompolypropylene/easily hydro - degraded polyester (PP/EHDPET) blend fibers, in which file EHDPET compo-nent is degradable by treating with NaOH - H<sub>2</sub&g... Ultrafine polypropylene fibers are prepared frompolypropylene/easily hydro - degraded polyester (PP/EHDPET) blend fibers, in which file EHDPET compo-nent is degradable by treating with NaOH - H<sub>2</sub>O solu-tion. We investigated the morphology of PP/EHDPETblend fibers before and after stretching and alkalinehydrolysis. Then thermal behavior of the blend has alsobeen studied. 展开更多
关键词 POLYPROPYLENE Easily hydro - degraded POLYESTER BLEND fiber MORPHOLOGY
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Alkaline Hydrolysis of PP/EHDPET Blend Fibers
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作者 李梅 付中玉 +1 位作者 张大省 王庆瑞 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期44-47,共4页
Polypropylene superfine fibers or cell porous fibers were prepared from the bi-component blend fibers of polypropylene/easlly hydro-degraded polyester(PP/EHDPET)by alkaline hydrolysis process. EHDPET is a kind of copo... Polypropylene superfine fibers or cell porous fibers were prepared from the bi-component blend fibers of polypropylene/easlly hydro-degraded polyester(PP/EHDPET)by alkaline hydrolysis process. EHDPET is a kind of copolyester that can be rapidly hydro-degraded in the hot alkaline solution. This paper discussed the kinetics of alkaline hydrolysis of EHDPET, and the effect of catalyst, bulk ratio and the content of polypropylene grafted maleic anhydride (PP-g-MAH) on the alkaline hydrolysis process. Meanwhile, the morphological change of the outer surface of blend fibers during this process was also investigated by the technology of scanning electron microscope (SEM). 展开更多
关键词 POLYPROPYLENE ( PP) easily hydro - degraded POLYESTER (EHDPET) BLEND fibers ALKALINE hydroLYSIS .
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钛硅分子筛TS-1的制备工艺研究进展
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作者 刘桐 万辉 管国锋 《化工与医药工程》 2016年第1期1-4,共4页
钛硅分子筛(TS-1)能够高效地催化环己酮氨肟化反应从而使得其工艺流程大幅简化。水热合成法为TS-1合成的主要方法,碱性溶液改性处理可在一定程度上提高TS-1的催化性能,弥补不同生产批次TS-1催化性能稳定性差的不足。在TS-1中引入磁核是... 钛硅分子筛(TS-1)能够高效地催化环己酮氨肟化反应从而使得其工艺流程大幅简化。水热合成法为TS-1合成的主要方法,碱性溶液改性处理可在一定程度上提高TS-1的催化性能,弥补不同生产批次TS-1催化性能稳定性差的不足。在TS-1中引入磁核是近期发展迅速的一种新的TS-1改性方法,保证了良好的催化活性的同时体现出了良好的分离性能,为己内酰胺绿色生产技术的发展提供了新的思路。 展开更多
关键词 钛硅分子筛TS-1 水热合成 改性 磁载钛硅分子筛 绿色化学
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Chemial Bond and Stability of Adsorption of [Au(AsS_3)]^(2-)on the Surface of Kaolinite
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作者 闵新民 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2004年第1期5-8,共4页
Density function theory and discrete variation method (DFT-DVM) were used to study the adsorption of [Au(AsS 3)] 2- on the surface of kaolinite.The correlation among structure,chemical bond and stability was discuss... Density function theory and discrete variation method (DFT-DVM) were used to study the adsorption of [Au(AsS 3)] 2- on the surface of kaolinite.The correlation among structure,chemical bond and stability was discussed.Several models were selected with [Au(AsS 3)] 2- in different directions and sites.The results show that the models with gold on the edge of kaolinite basal layer contain pincerlike bond among gold and several oxygen atoms and form strong Au-O covalent bond,so these models are more stable than those with gold above or under the layer.The models with gold near to [AlO 2(OH) 4] octahedra are more stable than those with gold near to the vacancy without aluminium.These two stable tendencies in kaolinite-[Au(AsS 3)] 2- are stronger than that in kaolinite-Au systems.The interaction between [Au(AsS 3)] 2- and kaolinite is stronger than that between gold and kaolinite,and this interaction is strong enough to form the surface complexes. 展开更多
关键词 kaolinite-[Au(AsS 3)] 2- structure chemical bond STABILITY quantum chemistry calculation
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3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine.Structure and energy abilities as a component of solid composite propellants
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作者 Anatoly G.Korepin Natalia M.Glushakova +6 位作者 David B.Lempert Anatoly I.Kazakov Gennady V.Shilov Denis V.Korchagin Vadim M.Volokhov Elena S.Amosova Sergey M.Aldoshin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第7期1148-1155,共8页
The work addresses to the study of the molecular and crystal structure and properties of a new energyintensive compound 3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine(NBTAT),first obtained by the authors in 2... The work addresses to the study of the molecular and crystal structure and properties of a new energyintensive compound 3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine(NBTAT),first obtained by the authors in 2020.NBTAT compound crystallizes in the monoclinic system,space group P2(1)/n,density at room temperature 1.939 g/cm^(3).The energies of crystal packing and pairwise intermolecular interactions in NBTAT and its unnitrated analogue BTAT were calculated,and their comparative analysis was carried out.The enthalpy of formation of NBTAT molecules was calculated by quantum-chemical methods using Gaussian 09,and the enthalpy of formation of NBTAT in the solid phase(618 kJ/mol)was estimated.The energy capabilities of NBTAT as an oxidizer of solid composite propellants are estimated.It is shown that in metal-free compositions NBTAT is significantly superior to ammonium perchlorate(AP),dinitramide ammonium salt(ADN),HMX,BTAT at all stages of rocket systems,and is comparable to the superdense CL-20 yielding to the latter at the lower stages and slightly winning at the upper stages. 展开更多
关键词 Nitrogen heterocycles Quantum chemistry Enthalpy of formation 3 6-bis(2 2 2-trinitroethylnitramino)-1 2 4 5-tetrazine Crystal structure Energetic ability
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4-methoxy-2,6-bis(3,5-dimethylpyrazoyl)-1,3,5-triazine modified carbon paste electrode for trace Cu(Ⅱ) determination by differential pulse volt-ammetry
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作者 YANGSheng LUXiaoquan +2 位作者 XUEZhonghua FENGXiaoqiang WANGXiaofeng 《Rare Metals》 SCIE EI CAS CSCD 2003年第4期250-253,共4页
A differential pulse voltammetric method was developed for the sensitive andselective determination of Cu(II) at 4-methoxy-2,6-bis(3,5-dimethylpyrazoyl)-l,3,5-triazine modifiedcarbon paste electrode in 0.05 mol/L KHC_... A differential pulse voltammetric method was developed for the sensitive andselective determination of Cu(II) at 4-methoxy-2,6-bis(3,5-dimethylpyrazoyl)-l,3,5-triazine modifiedcarbon paste electrode in 0.05 mol/L KHC_8H_4O_4 solution (pH = 4.02). The oxidation peak of Cu(II)was observed at 0.065 V(vs Ag/AgCl) by scanning the potential in positive direction. The analysisprocedure consisted of an open circuit accumulation step in stirred sample solution. It was followedby medium exchange to a clean solution and subsequently an anodic potential scan was affected toobtain the voltammetric peak. The current was proportional to the concentration of the Cu(II) ion ina range of 1 X 10^(-7) -1 X 10^(-4) mol/L for 6 min accumulation; the most of metal ions did notinterfere with the determination. The developed method was applied to Cu (II) determination incoal-ash sample, the results agreed with that of atomic adsorption spectroscopy (AAS). 展开更多
关键词 analysis chemistry 4-Methoxy-2 6-bis (3 5-dimethylpyrazoyl)-1 3 5-triazine differential pulse voltammetry copper (II)
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Mineral Chemistry and Nomenclature of Amphiboles of Garnet Bearing Amphibolites From Thana Bhilwara,Rajasthan,India
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作者 H.Thomas Haritabh Rana 《Journal of Geological Research》 2020年第2期34-40,共7页
Amphiboles are frequently observed in the medium to high grade metamorphic rocks of garnet bearing amphibolites from Thana.In present work,authors have discussed the mineral chemistry and nomenclature of amphiboles.On... Amphiboles are frequently observed in the medium to high grade metamorphic rocks of garnet bearing amphibolites from Thana.In present work,authors have discussed the mineral chemistry and nomenclature of amphiboles.On the basis of mineral chemistry,the amphibole from garnet bearing amphibolite are normally varies from Hastingsite,Ferropargasite to Tschermakite variety. 展开更多
关键词 Mineral chemistry GARNET - AMPHIBOLITE NOMENCLATURE and Thana-Rajasthan
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