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Natural forests exhibit higher organic carbon concentrations and recalcitrant carbon proportions in soil than plantations:a global data synthesis
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作者 Xiuqing Nie Hui Wang +1 位作者 Jian Wang Shirong Liu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期131-141,共11页
Different chemical compositions of soil organic carbon(SOC)affect its persistence and whether it signifi-cantly differs between natural forests and plantations remains unclear.By synthesizing 234 observations of SOC c... Different chemical compositions of soil organic carbon(SOC)affect its persistence and whether it signifi-cantly differs between natural forests and plantations remains unclear.By synthesizing 234 observations of SOC chemical compositions,we evaluated global patterns of concentra-tion,individual chemical composition(alkyl C,O-alkyl C,aromatic C,and carbonyl C),and their distribution even-ness.Our results indicate a notably higher SOC,a markedly larger proportion of recalcitrant alkyl C,and lower easily decomposed carbonyl C proportion in natural forests.How-ever,SOC chemical compositions were appreciably more evenly distributed in plantations.Based on the assumed con-ceptual index of SOC chemical composition evenness,we deduced that,compared to natural forests,plantations may have higher possible resistance to SOC decomposition under disturbances.In tropical regions,SOC levels,recalcitrant SOC chemical composition,and their distributed evenness were significantly higher in natural forests,indicating that SOC has higher chemical stability and possible resistance to decomposition.Climate factors had minor effects on alkyl C in forests globally,while they notably affected SOC chemi-cal composition in tropical forests.This could contribute to the differences in chemical compositions and their distrib-uted evenness between plantations and natural stands. 展开更多
关键词 Global data synthesis Natural forest Plantations Soil organic carbon Soil organic carbon chemical composition
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Microwave-assisted Synthesis of Al_(4)SiC_(4) and Its Effect on Properties of MgO-C Refractories
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作者 WANG Li LIU Shijie +7 位作者 WEI Haoyu GUO Yanyan GENG Shangrui YAN Miaoxin QIN Feng GUO Yusen Ma Juanjuan DONG Binbin 《China's Refractories》 CAS 2024年第1期14-17,共4页
Al_(4)SiC_(4) was synthesized from Al powder, silicon carbide, and graphite by microwave sintering, and characterized by XRD and SEM. Then the synthesized material was added to the magnesia carbon refractory brick to ... Al_(4)SiC_(4) was synthesized from Al powder, silicon carbide, and graphite by microwave sintering, and characterized by XRD and SEM. Then the synthesized material was added to the magnesia carbon refractory brick to study its effect on the oxidation resistance, apparent porosity, bulk density, elastic modulus, and modulus of rupture. It is found that Al_(4)SiC_(4) can be synthesized by microwave sintering at 1 300 ℃ and the addition of Al_(4)SiC_(4)-containing material as an antioxidant can enhance the oxidation resistance of the magnesia carbon refractory brick. 展开更多
关键词 microwave-assisted synthesis Al_(4)SiC_(4) MgO-C refractories oxidation resistance
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Mass-Based Environmental Factor and Energy Assessment of Microwave-Assisted Synthesized Transition Metal Nanostructures
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作者 Victor J. Law 《American Journal of Analytical Chemistry》 CAS 2024年第6期201-218,共18页
This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy... This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy budget (measured in kJ) on the horizontal axes and process density (measured in kJg−1) on the vertical axes. These two axes allow both mass usage efficiency (Environmental-Factor) and energy efficiency to be evaluated for a range of microwave applicator and metal synthesis. The metrics are allied to the: second, sixth and eleventh principle of the twelve principle of Green Chemistry. This analytical approach to microwave synthesis (widely considered as a useful Green Chemistry energy source) allows a quantified dynamic environmental quotient to be given to renewable plant-based biomass associated with the reduction of the metal precursors. Thus allowing a degree of quantification of claimed “eco-friendly” and “sustainable” synthesis with regard to waste production and energy usage. 展开更多
关键词 microwave-assisted synthesis Transition Metals Nanostructures Allometry Scaling Power-Law Signature Green Chemistry
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Microwave-Assisted Solid Phase Organic Synthesis. Application to Indole Library Construction 被引量:3
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作者 DAI Wei-Min SUN Li-Ping +1 位作者 GUO Dian-Shun HUANG Xiang-Hong 《合成化学》 CAS CSCD 2004年第z1期103-103,共1页
关键词 MICROWAVE solid-phase organic synthesis combinatorial chemistry indole library.
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Synthesis strategies of covalent organic frameworks: An overview from nonconventional heating methods and reaction media
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作者 Jing Xiao Jia Chen +2 位作者 Juewen Liu Hirotaka Ihara Hongdeng Qiu 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第6期1596-1618,共23页
Covalent organic frameworks(COFs), as an emerging class of porous crystalline materials constructed by covalent links between the building monomers, have gained tremendous attention. Over the past 15 years, COFs have ... Covalent organic frameworks(COFs), as an emerging class of porous crystalline materials constructed by covalent links between the building monomers, have gained tremendous attention. Over the past 15 years, COFs have made rapid progress and substantial development in the chemistry and materials fields. However, the synthesis of COFs has been dominated by solvothermal methods for a long time and it usually involves high temperature, high pressure and toxic organic solvents, which created many challenges for environmental considerations. Recently,the exploration of new approaches for facile fabrication of COFs has aroused extensive interest. Hence, in this review, we comprehensively describe the synthetic strategies of COFs from the aspects of nonconventional heating methods and reaction media. In addition, the advantages,limitations and properties of the preparation methods are compared. Finally, we outline the main challenges and development prospects of the synthesis of COFs in the future and propose some possible solutions. 展开更多
关键词 Covalent organic frameworks Heating methods Reaction media synthesis strategy Formation mechanism
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Water-based synthesis of nanoscale hierarchical metal-organic frameworks:Boosting adsorption and catalytic performance
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作者 Yi Yu Zewei Liu +3 位作者 Xiaofei Chen Shujun Liu Chongxiong Duan Hongxia Xi 《Nano Materials Science》 EI CAS CSCD 2023年第4期361-368,共8页
The combination of nano sizes,large pore sizes and green synthesis is recognized as one of the most crucial and challenging problems in constructing metal-organic frameworks(MOFs).Herein,a water-based strategy is prop... The combination of nano sizes,large pore sizes and green synthesis is recognized as one of the most crucial and challenging problems in constructing metal-organic frameworks(MOFs).Herein,a water-based strategy is proposed for the synthesis of nanoscale hierarchical MOFs(NH-MOFs)with high crystallinity and excellent stability.This approach allows the morphology and porosity of MOFs to be fine tuned,thereby enabling the nanoscale crystal generation and a well-defined hierarchical system.The aqueous solution facilitates rapid nucleation kinetics,and the introduced modulator acts as a deprotonation agent to accelerate the deprotonation of the organic ligand as well as a structure-directing agent(SDA)to guide the formation of hierarchical networks.The assynthesized NH-MOFs(NH-ZIF-67)were assessed as efficient adsorbents and heterogeneous catalysts to facilitate the diffusion of guest molecules,outperforming the parent microZIF-67.This study focuses on understanding the NH-MOF growth rules,which could allow tailor-designing NH-MOFs for various functions. 展开更多
关键词 Nanoscale hierarchical metal-organic framework Water-based synthesis Volatile organic compounds Olefins oxidation
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Microwave-Assisted Au and Ag Nanoparticle Synthesis: An Energy Phase-Space Projection Analysis
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作者 Victor J. Law Denis P. Dowling 《American Journal of Analytical Chemistry》 CAS 2023年第4期149-174,共26页
Microwave-assisted synthesis of gold and silver nanoparticles, as a function of Green Chemistry, non Green Chemistry, and four applicator types are reported. The applicator types are Domestic microwave ovens, commerci... Microwave-assisted synthesis of gold and silver nanoparticles, as a function of Green Chemistry, non Green Chemistry, and four applicator types are reported. The applicator types are Domestic microwave ovens, commercial temperature controlled microwave chemistry ovens (TCMC), digesters, and axial field helical antennae. For each of these microwave applicators the process energy budget where estimated (Watts multiplied by process time = kJ) and energy density (applied energy divided by suspension volume = kJ·ml<sup>-1</sup>) range between 180 ± 176.8 kJ, and 79.5 ± 79 kJ·ml<sup>-1</sup>, respectively. The axial field helical field an-tenna applicator is found to be the most energy efficient (0.253 kJ·m<sup>-1</sup> per kJ, at 36 W). Followed by microwave ovens (4.47 ± 3.9 kJ·ml<sup>-1</sup> per 76.83 ± 39 kJ), and TCMC ovens (2.86 ± 2.3 kJ·m<sup>-1</sup> per 343 ± 321.5 kJ). The digester applicators have the least energy efficiency (36.2 ± 50.7 kJ·m<sup>-1</sup> per 1010 ± 620 kJ). A comparison with reconstructed ‘non-thermal’ microwave oven inactivation microorganism experiments yields a power-law signature of n = 0.846 (R<sup>2</sup> = 0.7923) four orders of magnitude. The paper provides a discussion on the Au and Ag nanoparticle chemistry and bio-chemistry synthesis aspects of the microwave applicator energy datasets and variation within each dataset. The visual and analytical approach within the energy phase-space projection enables a nanoparticle synthesis route to be systematically characterized, and where changes to the synthesis are to be mapped and compared directly with historical datasets. In order to help identify lower cost nanoparticle synthesis, in addition to potentially reduce synthesis energy to routes informed changes to potentially reduce synthesis energy budget, along with nanoparticle morphology and yield. 展开更多
关键词 Turkevich microwave-assisted synthesis Ag AU HYDROXYAPATITE Nanoparticle FUNCTIONALIZATION Energy Phase-Space Projection
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Green Chemistry Allometry Test of Microwave-Assisted Synthesis of Transition Metal Nanostructures
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作者 Victor J. Law Denis P. Dowling 《American Journal of Analytical Chemistry》 CAS 2023年第11期493-518,共26页
Microwave irradiation is considered an important approach to Green Chemistry, because of its ability to rapidly increase the internal temperature of polar-organic compounds that lead to synthesis times of minutes rath... Microwave irradiation is considered an important approach to Green Chemistry, because of its ability to rapidly increase the internal temperature of polar-organic compounds that lead to synthesis times of minutes rather than hours when compared to conventional thermal heating. This works describes a dual allometry test for the discrimination between the solvents and reagents used in the microwave-assisted synthesis of transition metal (zinc oxide, palladium silver, platinum, and gold) nanostructures. The test is performed in log-log process energy phase-space projection, where the synthesis data (kJ against kJ·mol<sup>-1</sup>) has a power-law signature. The test is shown to discriminate between recommended Green Chemistry, problematic Green Chemistry, and Green Chemistry hazardous solvents. Typically, recommended Green chemistry exhibits a broad y-axes distribution within an upper exponent = 1 and lower exponent = 0.5. Problematic Green Chemistry exhibits a y-axes narrower distribution with an upper exponent = 0.94 and lower exponent = 0.64. Non-Green Chemistry hazardous data exhibits a further narrowing of the y-axes distribution within upper exponent = 0.87 and lower exponent = 0.66. In all three cases, the y-axes is aligned to original database power-law signature. It is also shown that in the x-axes direction (process energy budget) the grouped order of magnitude decreases from four orders for recommended Green Chemistry solvent and reagent data, through two orders for non-Green Chemistry hazardous material and down to one order for problematic Green Chemistry. 展开更多
关键词 microwave-assisted synthesis Transition Metals Nanostructures Allometry Scaling Power-Law Signature Green Chemistry
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Microwave-Assisted Transition Metal Nanostructure Synthesis: Power-Law Signature Verification
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作者 Victor J. Law Denis P. Dowling 《American Journal of Analytical Chemistry》 2023年第8期326-349,共24页
A power-law (y = cx<sup>n</sup>) signature between process energy budget (kJ) and process energy density (kJ·ml<sup>-1</sup>) of microwave-assisted synthesis of silver and gold nanostructu... A power-law (y = cx<sup>n</sup>) signature between process energy budget (kJ) and process energy density (kJ·ml<sup>-1</sup>) of microwave-assisted synthesis of silver and gold nanostructures has been recently described [Law and Denis. AJAC, 14(4), 149-174, (2023)]. This study explores this relation further for palladium, platinum, and zinc oxide nanostructures. Parametric cluster analysis and statistical analysis is used to test the power-law signature of over four orders of magnitude as a function of six microwave applicator-types metal precursor, non-Green Chemistry synthesis and claimed Green Chemistry. It is found that for the claimed Green Chemistry, process energy budget ranges from 0.291 to 900 kJ, with a residual error ranging between −33 to +25.9 kJ·ml<sup>-1</sup>. The non-Green Chemistry synthesis has a higher process energy budget range from 3.2 kJ to 3.3 MJ, with a residual error of −33.3 to +245.3 kJ·ml<sup>-1</sup>. It is also found that the energy profile over time produced by software controlled digestion applicators is poorly reported which leads to residual error problematic outliers that produce possible phase-transition in the power-law signature. The original Au and Ag database and new Pd, Pt and ZnO database (with and without problematic outliers) yield a global microwave-assisted synthesis power-law signature constants of c = 0.7172 ± 0.3214 kJ·ml<sup>-1</sup> at x-axes = 0.001 kJ, and the exponent, n = 0.791 ± 0.055. The information in this study is aimed to understand variations in historical microwave-assisted synthesis processes, and develop new scale-out synthesis through process intensification. 展开更多
关键词 microwave-assisted synthesis PD Ag Pt AU ZnO POWER-LAW Residual Error Statistical Analysis Parametric Cluster Analysis
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Microwave-assisted synthesis of asymmetric thiocarbonohydrazones under solvent-free conditions 被引量:5
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作者 Qing Han Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第7期793-796,共4页
Six new asymmetric thiocarbonohydrazones 3a-3f were synthesized from following steps: firstly hydrazine hydrate reacted with carbon disulfide to form thiocarbonohydrazide (1) under microwave irradiation. Then compo... Six new asymmetric thiocarbonohydrazones 3a-3f were synthesized from following steps: firstly hydrazine hydrate reacted with carbon disulfide to form thiocarbonohydrazide (1) under microwave irradiation. Then compound (1) reacted with ketone and different aldehydes step by step to give 3a-3f with excellent yields under solvent-free conditions using microwave irradiation. Their structures have been determined by elemental analysis, IR, MS and ^1H NMR data. 2009 Qing Han Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 Thiocarbonohydrazide Asymmetric thiocarbonohydrazones Microwave irradiation SOLVENT-FREE organic synthesis
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Recent advances in the synthesis of nanoscale hierarchically porous metal–organic frameworks 被引量:6
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作者 Chongxiong Duan Kuan Liang +8 位作者 Zena Zhang Jingjing Li Ting Chen Daofei Lv Libo Li Le Kang Kai Wang Han Hu Hongxia Xi 《Nano Materials Science》 EI CAS CSCD 2022年第4期351-365,共15页
Nanoscale hierarchically porous metal–organic frameworks(NHP-MOFs)have received unprecedented attention in many fields owing to their integration of the strengths of nanoscale size(<1μm)and hierarchical porous st... Nanoscale hierarchically porous metal–organic frameworks(NHP-MOFs)have received unprecedented attention in many fields owing to their integration of the strengths of nanoscale size(<1μm)and hierarchical porous structure(micro-,meso-and/or macro-pores)of MOFs.This review focuses on recent advances in the main synthetic strategies for NHP-MOFs based on different metal ions(e.g.,Cu,Fe,Co,Zn,Al,Zr,and Cr),including the template method,composite technology,post-synthetic modification,in situ growth and the grind method.In addition,the mechanisms of synthesis,regulation techniques and the advantages and disadvantages of various methods are discussed.Finally,the challenges and prospects of the commercialisation of promising NHP-MOFs are also presented.The purpose of this review is to provide a road map for future design and development of NHP-MOFs for practical application. 展开更多
关键词 Metal–organic frameworks NANOSCALE Hierarchically porous structure synthesis strategies
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Organic‐free synthesis of MOR nanoassemblies with excellent DME carbonylation performance 被引量:3
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作者 Kaipeng Cao Dong Fan +7 位作者 Shu Zeng Benhan Fan Nan Chen Mingbin Gao Dali Zhu Linying Wang Peng Tian Zhongmin Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第9期1468-1477,共10页
Seed‐assisted low alkalinity gel system was developed to explore the organic‐free synthesis of MORzeolite.MOR nanoassemblies with Si/Al ratio(SAR)up to 9.4 and high solid yield(84–94%)weresuccessfully obtained unde... Seed‐assisted low alkalinity gel system was developed to explore the organic‐free synthesis of MORzeolite.MOR nanoassemblies with Si/Al ratio(SAR)up to 9.4 and high solid yield(84–94%)weresuccessfully obtained under controlled low alkalinity conditions.Characterization results demonstratethat the acid strength increases in parallel with the SAR,while the total acid amount and theproton distribution in the main channels and the side pockets are similar for the samples.The protondistribution in the H‐MOR is not straightforwardly related to the Na+distribution in theas‐synthesized MOR,implying the transfer of the protons among the oxygen sites of framework Tatom.Relative to low‐silica samples I‐5.3 and I‐7.4,sample I‐9.4 displays the best mass transferperformance and accessibility of the acid sites by pyridine due to its relatively low Al density andmild dealumination degree.Correspondingly,sample I‐9.4(pyridine‐modified catalyst)shows thebest activity with ca.100%selectivity of methyl acetate(MAc)in the DME carbonylation reaction.The high steady MAc yield(6.8 mmol/g/h)over sample I‐9.4 suggests the promising application ofMOR nanoassemblies synthesized by this economical organic‐free strategy. 展开更多
关键词 MOR zeolite organic‐free synthesis DME carbonylation ACIDITY Diffusion
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Effect of different organic compounds on the preparation of CaO-based CO_(2) sorbents derived from wet mixing combustion synthesis 被引量:3
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作者 Tong Luo Shaolong Liu +3 位作者 Cong Luo Xiaolei Qi Bowen Lu Liqi Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第8期157-169,共13页
CaO based sorbents have great potential for commercial use to capture CO_(2) of power plants.In the demand of producing sorbents with better cyclic performance,CaO-based sorbents derived from different kinds of calciu... CaO based sorbents have great potential for commercial use to capture CO_(2) of power plants.In the demand of producing sorbents with better cyclic performance,CaO-based sorbents derived from different kinds of calcium precursors,containing calcium carbonate(CC-CaO),calcium gluconate monohydrate(CG-CaO),calcium citrate(CCi-CaO)and calcium acetate monohydrate(CA-CaO),were tested cyclically and compared using simultaneous thermal analyzer(STA).And further study was conducted on the sorbents modified with citric acid monohydrate and 50%gluconic acid solution by wet mixing combustion synthesis.The modified sorbents showed better performance and higher pore parameters as well as porous microstructure with more organic acid added.After 20 cycles of carbonation and calcination,the C2CCi8(CaO:citric acid=2:8 by mass ratio)and C2G8(CaO:gluconic acid=2:8 by mass ratio)sorbent possess CO_(2) capture capacity of 0.45g·g^(-1)(g CO_(2) per g sorbents)and 0.52 g·g^(-1) respectively.The citric acid was more effective for modification than gluconic acid for extended 50 cycles.Furthermore,good linear relationship between CaO conversion and specific surface area as well as pore volume were determined,of which the specific surface area showed closer correlation with CaO conversion。 展开更多
关键词 CO_(2)capture Calcium precursors Wet mixing synthesis organic additives
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Synthesis and Spectral Properties of Mixed-Ligand Complexes of Lanthanide Perchlorate with Bis-(phenylsulfinyl)ethane and Organic Lewis Bases 被引量:1
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作者 张若桦 卜显和 +1 位作者 孙心琳 王永生 《Journal of Rare Earths》 SCIE EI CAS CSCD 1997年第2期11-15,共5页
Six lanthanide complexes with bis(phenylsulfinyl)ethane(bphse) and organic bases(phen: 1,10 phenanthroline and bipy: 2,2'-bipyridine) were synthesized and characterized by elemental analysis, conductance and spec... Six lanthanide complexes with bis(phenylsulfinyl)ethane(bphse) and organic bases(phen: 1,10 phenanthroline and bipy: 2,2'-bipyridine) were synthesized and characterized by elemental analysis, conductance and spectral (IR, UV Visible) data. The complexes were Ln(bphse) 2(bipy)(ClO 4) 3· n H 2O and Ln 2(bphse) 3(phen) 2(ClO 4) 6·H 2O(where Ln=Nd, Eu and Gd; n =0~2). IR spectral data confirmed that the lanthanide ions were coordinated by oxygen atoms from bphse and nitrogen atoms from phen or bipy. Exitation and emission spectra of Eu complexes were measured and discussed. 展开更多
关键词 Rare earths Complex synthesis Spectral properties Bis(phenylsulfinyl)ethane organic bases
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Synthesis and Crystal Structure of a Magnesium Metal-organic Framework 被引量:1
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作者 吴兆锋 冯美玲 +2 位作者 胡冰 黄小荥 赵玉宝 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第11期1585-1590,共6页
A magnesium metal organic framework, [N-H2(CH3)2][-N(CH3)4][Mgs(bpdc)3(O2CH)6]· 3H2O (1, bpdcH2 = 4,4'-biphenyldicarboxylic acid), has been solvothermally synthesized and structurally characterized. 1 ... A magnesium metal organic framework, [N-H2(CH3)2][-N(CH3)4][Mgs(bpdc)3(O2CH)6]· 3H2O (1, bpdcH2 = 4,4'-biphenyldicarboxylic acid), has been solvothermally synthesized and structurally characterized. 1 crystallizes in the trigonal system, space group R-3, with a = 11.3427(3), c = 41.5662(18) A, V = 4631.3(3) A^3, Z = 3 and the final R = 0.0457. Its structure features a pillared-layered three-dimensional network with 8.21 A cavities, in which cationic [NH2(CH3)2]^+ or [N(CH3)4]^+ and lattice water molecules are located. Thermal stability of the title compound has also been investigated. 展开更多
关键词 solvothermal synthesis MAGNESIUM metal organic framework crystal structure
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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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Synthesis of Single Hexagonal-Phase AlN Nanocrystallines by a Liquid-Solid Metathetical Reaction in an Organic Solution 被引量:1
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作者 颜国君 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2008年第3期334-337,共4页
A liquid-solid metathetical reaction method (LSMRM) of synthesizing AIN nanocrystallines is presented. AIN nanocrystallines made through LSMRM are characterized by X-ray diffractions (XRD), X-ray photoelectron spe... A liquid-solid metathetical reaction method (LSMRM) of synthesizing AIN nanocrystallines is presented. AIN nanocrystallines made through LSMRM are characterized by X-ray diffractions (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), Fourier transformation infrared (FT-IR) spectroscopy, and Raman spectroscopy. The results show that the samples are single hexagonal-phase AIN and the size of the AIN samples is about tens of nanometer. 展开更多
关键词 AIN nanocrystalline synthesis organic solvent thermal method
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Synthesis and Performance Evaluation of Organic Bentonite Modifier Dimethyldistearylammonium Bromide (DODMAB) 被引量:2
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作者 Qingwang Liu Ao Sun +3 位作者 Zhenzhong Fan Jiguang Wang Tong Zhang Dong Cheng 《Open Journal of Composite Materials》 2014年第4期220-223,共4页
Dimethyldistearylammonium Bromide (DODMAB) is a bentonite modifier with good performance. In this experiment, 1-Bromooctadecane is the raw material, and completes tertiary amination and quaternization successively by ... Dimethyldistearylammonium Bromide (DODMAB) is a bentonite modifier with good performance. In this experiment, 1-Bromooctadecane is the raw material, and completes tertiary amination and quaternization successively by changing the condition of experiment. The result is that the productivity can achieve 78.94% in the synthesis of DODMAB. It has been used in the experiment of bentonite modification and achieves good results;compared with using trimethylstearylammonium bromide as the organic modifier, the synthetic organic bentonite has better performance than the common organic modifier when used in the oil base drilling fluid of oilfield operation. 展开更多
关键词 organic MODIFIER STEPWISE synthesis Performance EVALUATION
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Asymmetric Synthesis of (-)-1-Trimethylsilyl-ethanol with Immobilized Saccharomyces Cerevisiae Cells in Water/Organic Solvent Diphasic System 被引量:2
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作者 娄文勇 宗敏华 范晓丹 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期136-140,共5页
Asymmetric synthesis of (-)-1-trimethylsilyl-ethanol with immobilized Saccharomyces cerevisiae cells in water/organic solvent biphasic system was studied. The effects of shake speed, hydrophobicity of organic solvent,... Asymmetric synthesis of (-)-1-trimethylsilyl-ethanol with immobilized Saccharomyces cerevisiae cells in water/organic solvent biphasic system was studied. The effects of shake speed, hydrophobicity of organic solvent, volume ratio of water phase to organic phase, pH value of aqueous phase and reaction temperature on the initial reaction rate, maximum yield and enantiomeric excess (ee) of the product were systematically explored. All the above-mentioned factors had significant influence on the reaction. n-Hexane was found to be the best organic solvent for the reaction. The optimum shake speed, volume ratio of water phase to organic phase, pH value and reaction temperature were 150 r.min-1, 1/2, 8 and 30 ℃ respectively, under which the maximum yield and enantiomeric excess of the product were as high as 96.8% and 95.7%, which are 15% and 16% higher than those of the corresponding reaction performed in aqueous phase. To our best knowledge, this is the most satisfactory result obtained. 展开更多
关键词 (-)-1-trimethylsilyl-ethanol immobilized cell Saccharomyces cerevisiae asymmetric synthesis ter/organic solvent biphase
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REDUCTION BY HYPOPHOSPHOROUS ACID IN ORGANIC SYNTHESIS 被引量:1
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作者 Xue WANG Ye Di GUAN 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第5期407-408,共2页
Hypophosphorous acid and its salt were found to serve as a new agent for selective reduction of α,β-unsaturated carbonyl compounds under mild reaction conditions.
关键词 ETOH HO ACID REDUCTION BY HYPOPHOSPHOROUS ACID IN organic synthesis
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