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Cr3+的水解聚合作用 Ⅵ.反丁烯二酸存在下低浓度铬的水解聚合

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化学学报 1985年第12期43卷 1138-1144页

作者：罗勤慧沈孟长丁益屠庆云戴安邦南京大学配位化学研究所南京大学配位化学研究所南京

铬（Ⅲ）离子与反丁烯二酸生成的羟联多核配合物可用作偶联剂,但其在溶液中的状态尚缺乏定量研究。本文用静置平衡pH法在四种不同浓度(0.00175,0.0025,0.00375和0.005mol·dm-3)的反丁烯二酸存在下和低铬浓度(0.0025mol·dm-3)时,研究了... 详细信息

铬（Ⅲ）离子与反丁烯二酸生成的羟联多核配合物可用作偶联剂,但其在溶液中的状态尚缺乏定量研究。本文用静置平衡pH法在四种不同浓度(0.00175,0.0025,0.00375和0.005mol·dm-3)的反丁烯二酸存在下和低铬浓度(0.0025mol·dm-3)时,研究了C3+在溶液中的状态,并用Newton-Raphson法和非线性最小平方法计算了在四种反丁烯二酸浓度下[Cr2OH]5+,[Cr2（OH）A]3+和[Cr2（OH）A2]+的水解常数和形成常数,在四种浓度下所得结果颇为一致。本文的结果对合成偶联剂和解释偶联作用的机理提供了线索。

关键词：平衡浓度质子化常数形成常数水解常数配合物金属离子 OH 丁烯二酸二元羧酸偶联剂 Cr

三价铬离子水解聚合作用的研究 Ⅶ.反丁烯二酸存在下高铬浓度区水解产物的pqr分析

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化学学报 1986年第6期44卷 568-574页

作者：罗勤慧沈孟长丁益屠庆云戴安邦南京大学配位化学研究所南京大学配位化学研究所南京

本文报道用静置平衡pH法研究在较高的铬浓度(cA=0.01,0.015,0.02mol·dm-3)存在下,Cr3+在水溶液中的状态.用Newton-Raphson法和非线性Gauss-Newten法进行优化处理,自编成LEMIT程序、用此程序在电子计算机上对铬配合物HpMqAr的组成进行pq... 详细信息

本文报道用静置平衡pH法研究在较高的铬浓度(cA=0.01,0.015,0.02mol·dm-3)存在下,Cr3+在水溶液中的状态.用Newton-Raphson法和非线性Gauss-Newten法进行优化处理,自编成LEMIT程序、用此程序在电子计算机上对铬配合物HpMqAr的组成进行pqr分析,求得粒子的最佳组成为[CrOH]2+,[Cr2OH]5+,[Cr（OH）A]和[Cr2（OH）A]3+.用此程序同时计算30个数据点,求得各粒子的水解常数,拟合结果良好,说明LEMIT程序能用于复杂体系的计算.

关键词：实验值计算值计算机配合物水解常数平衡浓度 pqr 金属离子水解产物铬浓度丁烯二酸二元羧酸

Phosphorus substitution into Co_(3)S_(4) nanoneedle arrays for efficient hydrogen evolution catalysis

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Journal of Materials Science & Technology 2021年第30期89卷 52-58页

作者： Zhangtao Guo Gaoqi Tian Lin Liu Binyu Zhang Qiang Wu Yang Cao Jinchun tu Lei ding Xiaolin Zhang State Key Laboratory of Marine Resource Utilization in South China Sea School of Materials Science and EngineeringHainan UniversityHaikou 570228China School of Tropical Medicine and Laboratory Medicine MOE Key Laboratory of Emergency and TraumaHainan Medical UniversityHaikou 571199China Key Laboratory Of Child Cognition&Behavior Development Of Hainan Province Qiongtai Normal UniversityHaikou 571127China

Transition-metal based hybrids with excellent stability and activity are favorable candidates for hydrogen evolution reaction(HER).The development of typical Co_(3)S_(4)has recently received considerable attention due to the multiple valences of the spinel-structured ***,the in-depth effect of the dopants on the HER performance of Co_(3)S_(4)has not been systematically ***,we report a sequential synthesis of a spinel-structured cobalt phosphosulfate nanoneedle arrays grown on carbon cloth(namely,P-Co_(3)S_(4)/CC).Results indicate that P-Co_(3)S_(4)/CC exhibits high electrocatalytic performance for HER with a low overpotential of 65 mV to drive10 mAcm……(-2),a small Tafel slope of 76.6 mV per decade,and great long-term stability for 25 h at various current densities in alkaline *** first-principle calculation result reveals that the phosphorous doping work at Co_(3)S_(4)enhances the HER performance significantly because the tetrahedral Co^(2+)active sites nearest the P atoms more easily weaken the H-O bond to form *** experiment result characterization and theoretical calculations further show that the introduction of P atom not only offers more active sites but also improves the electrical conductivity in an alkaline electrolyte ***,the identification of active species provides feasible guidance for the further design of high-performance spinel-structured catalysts.

关键词： P-Co_(3)S_(4)/CC P substitution Electronic conductivity HER

Facile fabrication of integrated three-dimensional C- MoSe2/reduced graphene oxide composite with enhanced performance for sodium storage

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Nano Research 2016年第6期9卷 1618-1629页

作者： Dong Xie Wangjia Tang Yadong Wang Xinhui Xia Yu Zhong ding Zhou DonghuangWang Xiuli Wang Jiangping tu State Key Laboratory of Silicon Materials Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province and School of Materials Science and Engineering Zhejiang University Hangzhou 310027 China School of Engineering Nanyang Polytechnic 569830 Singapore

Scrupulous design and fabrication of advanced electrode materials are vital for developing high-performance sodium ion batteries. Herein, we report a facile one-step hydrothermal strategy for construction of a C-MoSe2/rGO composite with both high porosity and large surface area. Double modification of MoSe2 nanosheets is realized in this composite by introducing a reduced graphene oxide （rGO） skeleton and outer carbon protective layer. The MoSe2 nanosheets are well wrapped by a carbon layer and also strongly anchored on the interconnected rGO network. As an anode in sodium ion batteries, the designed C-MoSe2/rGO composite delivers noticeably enhanced sodium ion storage, with a high specific capacity of 445 mAh-g-1 at 200 mA.g-1 after 350 cycles, and 228 mAh-g 1 even at 4 A.g-1; these values are much better than those of C-MoSe2 nanosheets （258 mAh.g-a at 200 mA-g-1 and 75 mAh-g-1 at 4 A.g-~）. Additionally, the sodium ion storage mechanism is investigated well using ex situ X-ray diffraction and transmission electron microscopy methods. Our proposed electrode design protocol and sodium storage mechanism may pave the way for the fabrication of other high-performance metal diselenide anodes for electrochemical energy storage.

关键词： molybdenum diselenide double modification carbon coating graphene skeleton sodium ion storage

Enzymatic Synthesis of a Diastereomer of Neoabyssomicin Derivative Using the Diels-Alderase AbyU

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Chinese Journal of Chemistry 2021年第7期39卷 1871-1877页

作者： Wenjuan ding Changbiao Chi Xiaoyi Wei Changli Sun Jiajia tu Ming Ma Qinglian Li Jianhua Ju CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology Guangdong Key Laboratory of Marine Materia MedicaRNAM Center for Marine MicrobiologySouth China Sea Institute of OceanologyChinese Academy of Sciences164 West Xingang RoadGuangzhouGuangdong510301 China College of Oceanology University of Chinese Academy of Sciences19 Yuquan RoadBeijing100049 China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) No.1119Haibin Rd.Nansha DistrictGuangzhouGuangdong510301 China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing100191 China Key Laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical GardenChinese Academy of SciencesGuangzhouGuangdong510650 China

Main observation and conclusion The enzyme AbyU catalyses a Diels-Alder(DA)reaction during abyssomicin C *** this study,AbyU is shown to convert the native substrate of another Diels-Alderase(DAase),AbmU,to a new abys... 详细信息

关键词： Biosynthesis Bioorganic chemistry Enzyme catalysis Neoabyssomicin Diels-Alderase

Behavior of rare earth elements in granitic profiles, eastern Tibetan Plateau, China

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Acta Geochimica 2017年第3期36卷 552-555页

作者： Lifeng Cui Zhiqi Zhao Congqiang Liu Sheng Xu Taoze Liu Chenglong tu Hu ding State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081 China Scottish Universities of Environmental Research Centre Glasgow G75 0QF UK

Rare earth elements(REEs) can record geologic and geochemical processes. We studied two granitic regolith profiles from different climatic zones in eastern Tibetan Plateau and found that(1)∑ RREEs ranged from119.65 to 275.33 mg/kg in profile ND and5.11–474.55 mg/kg in profile GTC, with average values of205.79 and 161 mg/kg, respectively. ∑RREEs was higher in accumulation horizon and semi-regolith;(2) Influenced by climate, the fractionation of light and heavy REEs(LREEs and HREEs) varied during weathering. The ratio of LREEs/HREEs in pedosphere was higher than semi-regolith in tropical profile;(3) A negative Eu anomaly in both profiles was the result of bedrock weathering. A positive Ce anomaly was observed in all layers of profile ND, and only in the upper 100 cm of profile GTC. This indicates that redox conditions along the regolith profile varied considerably with climate.(4) Normalized by chondrite,LREEs accumulated much more than HREEs; REE distribution curves were right-leaning with a V-type Eu anomaly in both profiles.

关键词： Chemical weathering Eu anomaly Critical zone Soil weathering

Characteristics of Electric Double Layer in Different Aqueous Electrolyte Solutions for Supercapacitors

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Wuhan University Journal of Natural Sciences 2012年第3期17卷 200-204页

作者： PAN Qun tu Wenmao ding Lan MI Guomin School of Resources and Environmental Engineering Wuhan University of Technology Wuhan 430070 Hubei China Dandong Scking Electronic Development Co. LTD Dandong 118000 Liaoning China

Aiming to find suitable electrolytes for electric double layer capacitor （EDLC）,the relationship between the formation velocity of electric double layer and the specific capacitance in different electrolyte （H 2 SO 4,KOH,KCl,NH 4 Cl,and LiOH） solutions was investigated by cyclic voltammetry and AC impedance with varying frequency and potential,which was also analyzed based on Stern model and Gouy-Chapman diffusion layer *** shows that the capacitance is positively correlated with the formation velocity of the electric double layers,which is affected by the type of ions applied,the concentration of the electrolyte solution,and the potential and frequencies as *** electrolyte solutions of 6 mol/L KOH and 4 mol/L H2SO4 provide the largest capacitance,reaching 214 and 186 μF/cm^ 2,*** 6 mol/L KOH and 4 mol/L H 2 SO 4 solutions are suitable electrolytes for EDLC applications using Pt as electrodes.

关键词： double electrode layer electrolyte supercapacitor AC impedance cyclic voltammetry

Characterization and distribution of polycyclic aromatic hydrocarbon in sediments of Haihe River, Tianjin, China

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Journal of Environmental Sciences 2007年第3期19卷 306-311页

作者： JIANG Bin ZHENG Hai-long HUANG Guo-qiang ding Hui LI Xin-gang SUO Hong-tu LI Rui School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China Jinzhou Petrochemical Co. Designing Institute Jinzhou 121001 China

In this study sediment samples were collected from 13 sites of Haihe River in Tianjin City, China, sixteen of priority polycyclic aromatic hydrocarbons （PAHs） listed in USEPA were analyzed by means of GC-MS. The total concentrations of PAH ranged from 774.81 to 255371.91 ng/g dw, and two to four rings of PAHs were dominant in sediment samples. Molecular ratios, such as phenanthrene/anthracene, fluoranthene/pyrene and low-molecular-weight PAH/high-molecular-weight PAH, were used to study the possible sources of pollution. It indicated a mixed pattern of parolytic and petrogenic inputs of PAHs in sediments in Haihe River. The petrogenic PAHs may be mainly derived from the leakage of refined products, e.g., gasoline, diesel fuel and fuel oil vehicle traffics or gas stations from urban area. The pyrolytic PAHs might be from the discharge of industrial wastewater and the emission of atmospheric particles from petrochemical factories. In addition, the levels of PAHs in the urban and industrial areas are far beyond the values reported from other rivers and marine systems reported. This situation may be due to polluted discharging from some petrochemical industrial manufactories and worse traffic conditions in Tianjin.

关键词： PAHs Haihe River sediments Tianjin

Unraveling the advantages of Pd/CeO_(2)single-atom catalysts in the NO+CO reaction by model catalysts

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Nano Research 2023年第7期16卷 8882-8892页

作者： Qian Xu Xingwang Cheng Ningqiang Zhang Yi tu Lihui Wu Haibin Pan Jun Hu Honghe ding Junfa Zhu Yadong Li Department of Chemistry Tsinghua UniversityBeijing 100084China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China College of Chemistry and Materials Science Anhui Normal UniversityWuhu 241002China

Selective catalytic reduction of NO by CO is challenging in environmental catalysis but attractive owing to the advantage of simultaneous elimination of NO and ***,model catalysts consisting of Pd nanoparticles(NPs)and single-atom Pd supported on a CeO_(2)(111)film grown on Cu(111)(denoted as Pd NPs/CeO_(2)and Pd_(1)/CeO_(2),respectively)were successfully prepared and characterized by synchrotron radiation photoemission spectroscopy(SRPES)and infrared reflection absorption spectroscopy(IRAS).The NO+CO adsorption/reaction on the Pd_(1)/CeO_(2)and Pd NPs/CeO_(2)catalysts were carefully investigated using SRPES,temperature-programmed desorption(TPD),and *** is found that the reaction products on both model catalysts are in good agreement with those on real catalysts,demonstrating the good reliability of using these model catalysts to study the reaction mechanism of the NO+CO *** the Pd NPs/CeO_(2)surface,N_(2)is formed by the combination of atomic N coming from the dissociation of NO on Pd NPs at higher temperatures.N_(2)O formation occurs probably via chemisorbed NO combined with atomic N on the *** on the single-atom Pd_(1)/CeO_(2)surface,no N_(2)O is *** 100%N_(2)selectivity may stem from the formation of O-N-N-O^(*)intermediate on the *** this study,direct experimental evidence for the reaction mechanisms of the NO+CO reaction is provided,which supports the previous density functional theory(DFT)calculations.

关键词： NO+CO reaction Pd/CeO_(2) model catalysts reaction mechanisms