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Intermolecular reductive coupling of aliphatic ketones with alkynes and alkenes by BCN photocatalysts

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Science China Chemistry 2025年第1期 181-185页

作者： Yanping Xia Luyang Sun Jiajia Cheng Sibo Wang Meifang Zheng Xinchen Wang State Key Laboratory of Photocatalysis on Energy and environment College of Chemistry Fuzhou University

A photocatalytic process was developed for intermolecular reductive coupling of aliphatic ketones with alkynes/alkenes to furnish tertiary alcohols. Mechanistic studies support that boron carbonitrides(BCN) promote the single electron reduction of unactivated aliphatic ketones to generate ketyl radicals with visible light irradiation, which then react with alkynes and alkenes to afford the allylic and aliphatic alcohols, respectively. The heterogeneous photocatalytic system is compatible with diverse substrates including pharmaceutical-related molecules(43 examples) with reusability and scale-up experiments, verifying the complementary synthetic utility of this method to the homogeneous catalysts.

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Universal design of three-dimensional porous graphene-iron based promotors for kinetically rationalized lithium-sulfur chemistry

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Journal of Energy Chemistry 2025年第1期100卷 192-200页

作者： Hua Gao Yunfeng Zhang Menglei Wang Ruoxuan Yang Shuai Feng Xuan Cao Yaping Zhang Zhongyuan Lu Yingze Song State Key Laboratory of environment-Friendly Energy Materials School of Materials and Chemistry Southwest University of Science and Technology School of Material Science and Engineering Henan University of Technology college of Chemistry and Chemical Engineering Taishan University

Lithium-sulfur （Li-S） batteries are widely deemed to be one of the most potential candidates for future secondary batteries because of their remarkable energy ***,notorious polysulfide shuttling and retarded sulfur reaction kinetics pose significant obstacles to the further application of Li-S *** rationally designed highly active electrocatalysts can facilitate polysulfide conversion,the universal and scalable synthesis strategies need to be ***,a universal synthetic strategy to construct a series of three-dimensional （3D） porous graphene-iron （3DGr-Fe） based electrocatalysts involving 3DGr-FeP,3DGr-Fe3C,and 3DGr-Fe3Se4is exploited for manipulating the Li-S redox *** has been observed that the implementation of a 3D porous Gr architecture leads to the well-designed conductive networks,while the uniformly dispersed iron nanoparticles introduce an abundance of active sites,fostering the lithium polysulfide conversion,thereby bolstering the overall electrochemical *** Li-S battery with the 3DGr-Fe based electrocatalyst exhibits remarkable capacity retention of 94.8%upon 100 times at 0.2 ***,the soft-packaged Li-S pouch cell based on such a 3DGr-Fe electrocatalyst delivers superior capacity of 1060.71 mA h g-1and guarantees for the continuous 30 min work of fan *** investigation gives comprehensive insights into the design,synthesis,and mechanism of 3DGr-Fe based electrocatalysts with high activity toward efficient and durable Li-S batteries.

关键词： Redox reactions

Thermally triggered topological polymerization in diacetylene-functionalized covalent organic framework toward enhanced memristive properties

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Science China Chemistry 2025年

作者： Panke Zhou Yuxing Huang Ziyue Yu Cong Zhang Qian Chen Yiping Li Chao Lin Xiong Chen State Key Laboratory of Photocatalysis on Energy and environment Key Laboratory of Advanced Carbon-Based Functional MaterialsCollege of Chemistry Fuzhou University

The development of stimuli-responsive switching memory devices and the elucidation of their switching mechanisms in specific environments are crucial for advancing the field of molecular electronics. Herein, we propose two distinct two-dimensional covalent organic frameworks (COFs), namely Py-EDA and Py-BDA, incorporating acetylene (-C≡C-) or diacetylene(-C≡C-C≡C-) moieties, respectively, targeting fabricate memory devices exhibiting stimuli-responsive switching *** findings demonstrate that the incorporation of acetylene units effectively modulates the electronic band structure and enhances the degree ofπ-conjugation, resulting in devices that exhibit typical bipolar nonvolatile memory performance. Notably,upon thermal treatment, the memory behavior of the ITO/Py-BDA/Ag device transitions to a write-once-read-many-times(WORM) mode, displaying decreased SET voltage, increased ON/OFF current ratio, and remarkable retention reliability and cycle stability. This switching behavior is attributed to the occurrence of interlayer solid-state topological polymerization at 350℃, leading to the transformation of diacetylene columnar arrays into enyne chains within Py-BDA, thereby further promoting interlayer charge transfer and separation.

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Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing Chen Chao Wu Xiaoling Liu Biao Meng Tao Chen Yu Han Jun Wang Shibo Xi Yu Zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) college of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Activation energy

Mercury bioaccumulation in fish in an artificial lake used to carry out cage culture

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Journal of environmental Sciences 2019年第4期31卷 352-359页

作者： Yongmin Wang Qing Xie Qinqin Xu Jinping Xue Cheng Zhang Dingyong Wang college of resources and environment Southwest University Chongqing Key Laboratory of Agricultural resources and environment

As a global toxic pollutant,mercury(Hg)bioaccumulation within food chain could be influenced by human *** typical fish species were collected from Changshou Lake,an artificial lake used to carry out cage fish culture,to investigate the C/N isotopic compositions and Hg bioaccumulation in *** results showed that the total Hg(THg)and methylmercury(MeHg)levels in fish muscles((56.03±43.96)and(32.35±29.57)ng/g,wet weight),comparable with those in most studies in China,were significantly lower than the international marketing limit(0.5 mg/kg).Past human input for cage culture in this lake led to abnormal^(15)N enrichment in food chain,as the quantitative trophic levels based onδ^(15)N were different with that classified by feeding *** phenomenon subsequently demonstrated that it should be considered thoughtfully with respect to the application of the traditional method for understanding Hg bioaccumulation power by the slope of log_(10)[Hg]withδ^(15)N regression in specific water body(i.e.,Changshou Lake).In addition,no significant linear correlation between Hg and body weight or length of some fish species was observed,suggesting that the fish growth in the eutrophic environment was disproportionate with Hg bioaccumulation,and fish length or weight was not the main factor affecting Hg transfer with food *** occurrence of human disturbance in aquatic system presents a challenge to a better understanding of the Hg bioaccumulation and biomagnification within the food chain.

关键词： Mercury Methylmercury Human disturbed lake Bioaccumulation N enrichment

NUMERICAL SIMULATION OF GROUNDWATER DYNAMICS FOR SONGHUAJIANG RIVER VALLEY IN CHINA

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Journal of Hydrodynamics 2004年第3期16卷 332-335页

作者： ADIL Elkrail college of Water resources and environment

The study area was designed and constructed, based on the simplification of aconceptual model, to develop a three-dimensional groundwater flow model for simulation oftwo-layers system. Finite difference groundwater flow model was constructed for the CentralSonghuajiang River alluvial plain in Northeast China, with the coverage of 786. 6km^2. The gridnetworks with a spacing of 474. 4m by 509. 5m were used to cover the model area. The trial-and-errortechnique was used to calibrate the model. The sensitivity of the simulations to the modelparameters was studied -and the most sensitive parameters that controlling the residual headsdistribution in the Songhuajiang River valley were defined.

关键词： groundwater simulation model sensitivity calibration

Characteristics of volatile compounds removal in biogas slurry of pig manure by ozone oxidation and organic solvents extraction

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Journal of environmental Sciences 2013年第9期25卷 1800-1807页

作者： Yujun Wang Lianshuang Feng Xiaosong Zhao Xiulan Ma Jingmin Yang Huiqing Liu Sen Dou Miping Zhou Zhonglei Xie college of resources and environment Jilin Agricultural University Development college Jilin Agricultural University college of environment and resources Jilin University

Biogas slurry is not suitable for liquid fertilizer due to its high amounts of volatile materials being of complicated composition and peculiar smell. In order to remove volatiles from biogas slurry efficiently, the dynamic headspace and gas chromatography-mass spectrometry were used to clear the composition of volatiles. Nitrogen stripping and superfluous ozone were also used to remove volatiles from biogas slurry. The results showed that there were 21 kinds of volatile compounds in the biogas slurry, including sulfur compounds, organic amines, benzene, halogen generation of hydrocarbons and alkanes, some of which had strong peculiar smell. The volatile compounds in biogas slurry can be removed with the rate of 53.0% by nitrogen stripping and with rate of 81.7% by the oxidization and stripping of the superfluous ozone. On this basis, the removal rate of the volatile compounds reached 99.2% by chloroform and n-hexane extraction, and almost all of odor was eliminated. The contents of some dissolved organic compounds decreased obviously and however main plant nutrients had no significant change in the biogas slurry after being treated.

关键词： biogas slurry dynamic headspace removal volatile compounds plant nutrients

Bio-remediation of acephate–Pb(Ⅱ) compound contaminants by Bacillus subtilis FZUL-33

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Journal of environmental Sciences 2016年第7期28卷 94-99页

作者： Wenting Lin Zhen Huang Xuezhen Li Minghua Liu Yangjian Cheng The college of environment and resources Fuzhou University

Removal of Pb^（2＋）and biodegradation of organophosphorus have been both widely investigated respectively. However, bio-remediation of both Pb^（2＋）and organophosphorus still remains largely unexplored. Bacillus subtilis FZUL-33, which was isolated from the sediment of a lake, possesses the capability for both biomineralization of Pb^（2＋）and biodegradation of acephate. In the present study, both Pb^（2＋）and acephate were simultaneously removed via biodegradation and biomineralization in aqueous *** experiments were conducted to study the influence of p H, interaction time and Pb^（2＋）concentration on the process of removal of Pb2＋. At the temperature of 25°C, the maximum removal of Pb^（2＋）by B. subtilis FZUL-33 was 381.31 ± 11.46 mg/g under the conditions of p H 5.5, initial Pb^（2＋）concentration of 1300 mg/L, and contact time of 10 min. Batch experiments were conducted to study the influence of acephate on removal of Pb^（2＋）and the influence of Pb2＋on biodegradation of acephate by B. subtilis FZUL-33. In the mixed system of acephate–Pb2＋, the results show that biodegradation of acephate by B. subtilis FZUL-33 released PO43＋, which promotes mineralization of Pb2＋. The process of biodegradation of acephate was affected slightly when the concentration of Pb2＋was below 100 mg/L. Based on the results, it can be inferred that the B. subtilis FZUL-33 plays a significant role in bio-remediation of organophosphorus-heavy metal compound contamination.

关键词： Acephate–Pb2+ Bacillus subtilis Biodegradation Biomineralization

Preparation of nickel nanoparticles in emulsion

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中国有色金属学会会刊：英文版 2008年第1期18卷 212-216页

作者：张有贤付文杰安学勤 college of resources and environment Lanzhou University

The nickel nanoparticles with different sizes and spherical shape were prepared by the reduction of nickel sulfate with sodium borohydride in the water-in-oil emulsions of water/SDBS(sodium dodecylbenzene sulfonate)/n-pentanol/*** effects of aging time,molar ratio of water to SDBS(R)and the concentration of nickel sulfate on the size of particles were *** samples were characterized by transmission electron microscopy(TEM)and inductively coupled plasma spectrometry(ICP).The results show that the average particle size changes from 20 to 40 nm by adjusting aging time(15-30 min)and R(9-11.5).The concentration of nickel sulfate of 1.0 mol/L is the favorite condition.

关键词： W/O乳剂镍乳状液制备方法稀有金属