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Method to measure tree-ring width,density,elemental composition,and stable carbon and oxygen isotopes using one sample

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Journal of Forestry Research 2024年第3期35卷 167-174页

作者： Chenxi Xu Yaru Zhao Wenling An Qingyu Zhao yucheng liu Masaki Sano Takeshi Nakatsuka Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029People's Republic of China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044People's Republic of China College of Earth Sciences University of Chinese Academy of SciencesBeijing 100049People's Republic of China Graduate School of Environment Studies Nagoya UniversityNagoya 4648601Japan

Tree-ring width(RW),density,elemental com-position,and stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)are widely used as proxies to assess climate change,ecology,and environmental pollution;however,a specific pretreat-ment has been needed for each ***,we developed a method by which each proxy can be measured in the same ***,the sample is polished for ring width *** obtaining the ring width data,the sample is cut to form a 1-mm-thick wood *** sample is then mounted in a vertical sample holder,and gradually scanned by an X-ray ***,the count rates of the fluorescent photons of elements(for chemical characteriza-tion)and a radiographic grayscale image(for wood density)are obtained,*** density and the element content are ***,cellulose is isolated from the 1-mm wood plate by removal of lignin,and *** producing this cellulose plate,cellulose subsamples are separated by knife under the microscope for inter-annual and intra-annual stable carbon and oxygen isotope(δ^(13)C,δ^(18)O)*** on this method,RW,density,elemental composition,δ^(13)C,and δ^(18)O can be measured from the same sample,which reduces sample amount and treatment time,and is helpful for multi-proxy comparison and combination research.

关键词： Tree-ring width Tree-ring density Tree-ring elemental composition Tree-ring stable carbon and oxygenisotopes

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A mussel-induced approach to secondary functional cross-linking 3-aminopropytriethoxysilane to modify the graphene oxide membrane for wastewater purification

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Chinese Chemical Letters 2023年第1期34卷 426-434页

作者： Wenwen Tu yucheng liu Mingyan Chen Lili Ma Lingli Li Bing Yang College of Chemistry and Chemical Engineering Southwest Petroleum UniversityChengdu 610500China Research Institute of Industrial Hazardous Waste Disposal and Resource Utilization Southwest Petroleum UniversityChengdu 610500China

Graphene oxide(GO)with one-atom-thick exhibit remarkable molecule sieving properties,but its low permeance flux renders it difficult to be applied in practice as a high-permeance separation *** this study,we design complex membrane from covalently crosslinked GO,polydopamine(PDA),and 3-aminopropytriethoxysilane(APTES)as building blocks to fabricate the high-permeance GO-based membrane via the vacuum filtration method.A branched crosslinking product(PDA/APTES)working as a clamp grasped the hydrophilic functional groups(hydroxyl,epoxy,carboxyl)on GO for improving the GO membrane *** interlayer structure of the GO membrane was optimized according to the crosslinker concentration,reaction time,initial p H,and temperature for RGO/PDA/APTES(RGPA)in this *** the optimized reaction conditions including the crosslinker concentration of 1.4 m L/L,the temperature of 80°C,the time of 16 h,and the initial p H of 8.5 for RGPA mixture,the interlayer gallery of RGPA membrane was effectively tunes,endowing high flux ranging from 11.98 L m^(-2)h^(-1)to 1823.97 L m^(-2)h^(-1).Besides,the RGPA membrane ensured the high rejections to dye solutions such as methylene blue(MB)(>99%)and congo red(CR)(>90%).Meanwhile,the superior reusable performance of the RGPA membrane was achieved,together with the rejections for MB and CR to 96.32%and 93.1%after 4 cycles,***,the RGPA membrane possessed superior anti-fouling performances for bovine serum albumin(BSA)aqueous solution and excellent stabilities in harsh conditions(p H 3,7 and 11).Grafting the crosslinker onto GO nanosheets exhibits the distinct advantages of achieving the high flux,high rejections to dyes,and superior reusable performance of membranes,posing a great application potential for membrane separation technology in wastewater treatment.

关键词： Cross-linked graphene oxide Polydopamine APTES High flux membranes Dye separation

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Defect-rich and highly porous carbon nanosheets derived from Ti_(3)AlC_(2) MAX with good lithium storage properties

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Chinese Chemical Letters 2023年第2期34卷 618-622页

作者： Zhihao Zhu Peng liu yucheng liu Xingxing Gu Zhi Su Zhong Su Chao Lai College of Chemistry and Chemical Engineering Xinjiang Normal UniversityUrumqi 830054China School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhou 221116China Chongqing Key Laboratory of Catalysis and New Environmental Materials College of Environment and ResourcesChongqing Technology and Business UniversityChongqing 400067China National Research Base of Intelligent Manufacturing Service Chongqing Technology and Business UniversityChongqing 400067China

Defect-rich,highly porous two-dimensional carbon nanosheets(CNS) have attracted tremendous research interests in catalysis and environmental purification and other fields,because of their unique micromorphology,chemical stability and high specific surface ***,in this work,we report a new solution to synthesize an ultrathin two-dimensional CNS with rich defects and abundant pores via two-step etching the Ti_(3)AlC_(2)with the help of I2and *** CNS thickness,specific surface area and pore volume could be all tunable by adding the amount of *** the highest specific surface area and pore volume of the synthesized 2D CNS can be achieved 1134.4 m^(2)/g and 0.80 cm^(3)/g,with a thickness of only 0.64 nm and a yield of 35.9%.When employed as the anodes for lithium-ion batteries,the synthesized CNS anodes exhibit good cycling and rate *** work provides a novel and facile strategy for synthesizing highly porous and defective 2D carbon materials with good lithium storage properties.

关键词： Ti_(3)AlC_(2) Two-dimensional Carbon nanosheets Rich defect High specific surface area

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Determination of Salt Impurities in MDEA Solution Used in Desulfurization of Highly Sulphurous Natural Gas

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China Petroleum Processing & Petrochemical Technology 2015年第3期17卷 25-31页

作者： liu yucheng Zhang Bo Chen Mingyan Wu Danni Zhou Zheng School of Chemistry and Chemical Engineering Southwest Petroleum University Puguang Branch of Zhongyuan Oilfield Company

The foaming phenomenon of N-methyldiethanolamine(MDEA) solution used in desulfurization process occurs frequently in the natural-gas purification plant. The foaming phenomenon has a strong impact on operation of the process unit. The salt impurities are the main reason for causing the foaming of MDEA solution, so the full analysis of salt impurities is necessary. A method for comprehensive analysis of salt impurities in MDEA solution used in desulfurization process was established. Anions and non-metallic cations of MDEA solution were determined by different conditions of ion chromatograph, respectively. Metallic cations of the solution were detected by atomic absorption spectrophotometer with the N2O-C2H2 flame absorption. The analytical results of salt impurities in the desulfurization solution can provide a theoretical basis for an accurate analysis of the factors affecting the foaming of MDEA to unveil further control measures.

关键词： natural-gas purification plant MDEA solution salt impurities full analysis ion chromatograph

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High-quality industrial n-type silicon wafers with an efficiency of over 23% for Si heterojunction solar cells

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Frontiers in Energy 2017年第1期11卷 78-84页

作者： Fanying MENG Jinning liu Leilei SHEN Jianhua SHI Anjun HAN Liping ZHANG yucheng liu Jian YU Junkai ZHANG Rui ZHOU Zhengxin liu Research Center for New Energy Technology Shanghai Institute of Microsystem and Information Technology (SIMIT) Shanghai 200050 China Xi'an Longi Silicon Materials Corp. Xi'an 710100 China

n-type CZ-Si wafers featuring longer minority carrier lifetime and higher tolerance of certain metal contamination can offer one of the best Si-based solar cells. In this study, Si heterojuction （SHJ） solar cells which was fabricated with different wafers in the top, middle and tail positions of the ingot, exhibited a stable high efficiency of〉 22% in spite of the various profiles of the resistivity and lifetime, which demonstrated the high material utilization of n-type ingot. In addition, for effectively converting the sunlight into electrical power, the pyramid size, pyramid density and roughness of surface of the Cz-Si wafer were investigated by scanning electron microscope （SEM） and transmission electron microscope （TEM）. Furthermore, the dependence of SHJ solar cell open- circuit voltage on the surface topography was discussed, which indicated that the uniformity of surface pyramid helps to improve the open-circuit voltage and conversion efficiency. Moreover, the simulation revealed that the highest efficiency of the SHJ solar cell could be achieved by the wafer with a thickness of 100 μm. Fortunately, over 23% of the conversion efficiency of the SHJ solar cell with a wafer thickness of 100 μm was obtained based on the systematic optimization of cell fabrication process in the pilot production line. Evidently, the large availability of both n-type ingot and thinner wafer strongly supported the lower cost fabrication of high efficiency SHJ solar cell.

关键词： n-type Cz-Si thinner wafer surface texture,high efficiency SHJ solar cell

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Bifunctional trifluorophenylacetic acid additive for stable and highly efficient flexible perovskite solar cell

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InfoMat 2023年第10期5卷 43-52页

作者： Yang Cao Jiangshan Feng Zhuo Xu Lu Zhang Junjie Lou yucheng liu Xiaodong Ren Dong Yang Shengzhong(Frank)liu Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationSchool of Materials Science and EngineeringShaanxi Key Laboratoryfor Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy TechnologyInstitute for Advanced Energy MaterialsShaanxi NormalUniversityXi'anShaanxithe People's Republic of China Institute of Nanoscience and Nanotechnology School of Materials and EnergyLanzhou UniversityLanzhouGansuthe People's Republic of China Dalian National Laboratory for Clean Energy iChEMDalian Institute of Chemical PhysicsChinese Academy of SciencesDalianthe People'sRepublic of China University of Chinese Academy of Sciences Beijingthe People's Republic of China

The defects within perovskite films are the fatal roadblock limiting the performance of perovskite solar cells(PSCs).Herein,we develop a patching strategy to obtain high quality perovskite film using bifunctional trifuorophenylacetic acid(TFPA).Theoretical calculation and experiments reveal that the-COOH groups in TFPA effectively passivate the deep-energy-level defects of perovskite by combining with Pb clusters on the perovskite grain surfaces to enhance the efficiency of PSCs,and hydrophobic benzene groups containing fluorine in TFPA are exposed to improve the stability of *** power conversion effi-ciency(PCE)of PSCs with TFPA is enhanced from 22.95%to 24.56%.Most importantly,we successfully fabricated flexible PSCs using TFPA with the high PCE of 22.65%.The devices with TFPA maintain 93.22%of the initial efficiency MPP under continuous irradiation for 10.5 h,while the devices without TFPA only retain 82.22%of the initial efficiency under the same conditions for just 5 ***,the unsealed devices with TFPA hold 93.59%of the initial efficiency when stored in air for 3912 h.

关键词： additive flexible passivation perovskite solar cell stability

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De novo assembly of a Chinese soybean genome

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Science China(Life Sciences) 2018年第8期61卷 871-884页

作者： Yanting Shen Jing liu Haiying Geng Jixiang Zhang yucheng liu Haikuan Zhang Shilai Xing Jianchang Du Shisong Ma Zhixi Tian State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China Provincial Key Laboratory of Agrobiology Institute of Crop Germplasm and Biotechnology Jiangsu Academy of Agricultural Sciences Nanjing 210014 China School of Life Sciences University of Science and Technology of China Hefei 230027 China Berry Genomics Corporation Beijing 100015 China University of Chinese Academy of Sciences Beijing 100039 China

Soybean was domesticated in China and has become one of the most important oilseed crops. Due to bottlenecks in their introduction and dissemination, soybeans from different geographic areas exhibit extensive genetic diversity. Asia is the largest soybean market; therefore, a high-quality soybean reference genome from this area is critical for soybean research and ***, we report the de novo assembly and sequence analysis of a Chinese soybean genome for "Zhonghuang 13" by a combination of SMRT, Hi-C and optical mapping data. The assembled genome size is 1.025 Gb with a contig N50 of 3.46 Mb and a scaffold N50 of 51.87 Mb. Comparisons between this genome and the previously reported reference genome(cv. Williams82) uncovered more than 250,000 structure variations. A total of 52,051 protein coding genes and 36,429 transposable elements were annotated for this genome, and a gene co-expression network including 39,967 genes was also established. This high quality Chinese soybean genome and its sequence analysis will provide valuable information for soybean improvement in the future.

关键词： de novo soybean genome Zhonghuang 13 Gmax_ZH13 structure variation gene co-expression network

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A potential-driven switch of activity promotion mode for the oxygen evolution reaction at Co_(3)O_(4)/NiO_(x)H_(y) interface

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eScience 2022年第4期2卷 438-444页

作者： Wang Wang Zixu Wang Youcheng Hu yucheng liu Shengli Chen Electrochemical Power Sources Key Laboratory Department of ChemistryWuhan UniversityWuhan430072China Wuhan University Testing Center Wuhan UniversityWuhan430072China

Co_(3)O_(4)spinel oxides have manifested promising activity toward the oxygen evolution reaction(OER)through effective *** them to become top electrocatalysts,however,accurate accounts of the catalytic kinetics are essential to gain a deep understanding of the activity promotion ***,we use a newly proposed kinetic model based on energetic span as the rate-determining term for the electrocatalytic reaction to throw light on the promotion mechanism of Co_(3)O_(4)interfaced with nickel hydroxides(NiO_(x)H_(y))for the *** find that depending on the electrode potential,the OER kinetics at the designed interface between Co_(3)O_(4)and NiO_(x)H_(y)are boosted in entirely different *** a result,the OER can occur at a lower onset potential as well as a low Tafel *** work emphasizes the benefit of using rational theoretical models for electrocatalyst design.

关键词： Oxygen evolution reaction Interface engineering Double exchange interaction Potential-driven switch of mechanism Energetic span

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GenoBaits Soy40K:a highly flexible and low-cost SNP array for soybean studies

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Science China(Life Sciences) 2022年第9期65卷 1898-1901页

作者： yucheng liu Shulin liu Zhifang Zhang Lingbin Ni Xingming Chen Yunxia Ge Guoan Zhou Zhixi Tian State Key Laboratory of Plant Cell and Chromosome Engineering Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China MolBreeding Biotechnology Co. Ltd.Shijiazhuang 050035China University of Chinese Academy of Sciences Beijing 100039China

Dear Editor,Soybean(Glycine max[L.]Merr.)provides more than half of the oilseeds and more than a quarter of protein *** is estimated that the production of soybean has to be doubled by 2050 to meet the needs of the rapidly increasing consumption of soybean seeds along with a continuously increasing population(Ray et al.,2013).As such,development of a genotyping platform with high throughput,high efficiency and high precision but low-cost is urgently needed to accelerate soybean functional study and molecular design breeding.

关键词： soybean cost doubled

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Comparison of Spatial Forms between Villages under Different Cultures in Jiangxi Province

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Asian Agricultural Research 2020年第11期12卷 53-58页

作者： yucheng liu Jiangxi Normal University Nanchang 330022 China

Taking Meipi Village and Zhuqiao Village as the research objects,the external space,internal space and architecture form of the ancient villages were compared,and the law and essence of village pattern under different cultures were summarized in this article,so as to provide ideas for the preservation and continuation of Jiangxi's history and culture and innovative rural development.

关键词： Jiangxi Ancient village Form comparison

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