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杞麓湖孟氏螺蛳(Anularya mansuyi)壳体碳同位素记录的水体溶解无机碳变化

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湖泊科学 2024年第5期36卷 1436-1446页

作者：江戈平雷国良朱芸张文翔于源许丽红杜垚华李全聪孙婉婷福建师范大学湿润亚热带生态-地理过程教育部重点实验室福州350117 福建师范大学地理科学学院碳中和未来技术学院福州350117 福建师范大学稳定同位素中心福州350117 云南师范大学高原地理过程与环境变化云南省重点实验室昆明650500

湖泊中腹足类壳体碳酸盐的碳同位素与水体溶解无机碳密切相关,是研究区域湖泊水体碳循环的重要材料之一。滇中地区湖泊众多,然而该区域湖泊中水体溶解无机碳的变化特征仍不清楚。孟氏螺蛳壳体为滇中湖泊特有属,本文通过对杞麓湖现生孟... 详细信息

湖泊中腹足类壳体碳酸盐的碳同位素与水体溶解无机碳密切相关,是研究区域湖泊水体碳循环的重要材料之一。滇中地区湖泊众多,然而该区域湖泊中水体溶解无机碳的变化特征仍不清楚。孟氏螺蛳壳体为滇中湖泊特有属,本文通过对杞麓湖现生孟氏螺蛳壳体采集,并对其壳体沿生长方向开展碳酸盐δ~(13)C测试,尝试利用孟氏螺蛳壳体δ~(13)C分析杞麓湖水体溶解无机碳变化的变化特征。研究结果表明:(1)孟氏螺蛳壳体δ~(13)C与壳体生长环境密切相关,QLH-A与QLH-B在母体环境中的δ~(13)C平均值分别为-3.78‰与-5.55‰,变化幅度分别为2.07‰与3.03‰;在湖泊水体环境中的δ~(13)C平均值分别为-2.90‰与-3.28‰,变化幅度分别为1.81‰与1.74‰。(2)孟氏螺蛳在湖泊水体环境中生长时,壳体δ~(13)C记录了湖泊水体DIC的δ~(13)C_(DIC)变化特征,揭示出杞麓湖水体DIC主要受大气交换和湖泊中生物系统共同影响,其δ~(13)C_(DIC)在季节尺度变化不显著。(3)杞麓湖湖泊中大量水生藻类的死亡引起的有机质分解将导致湖泊水体δ~(13)C_(DIC)发生显著偏负变化,据此推断壳体δ~(13)C记录的偏负变化与云南2013年大旱期事件吻合,揭示出孟氏螺蛳壳体δ~(13)C具有记录湖泊生态系统自身重大变化的潜力。孟氏螺蛳古螺壳在滇中湖泊广泛分布,本文研究结果将有利于基于地层中的壳体识别地质历史时段滇中湖泊水体DIC特征及其湖泊生态系统的变化。

关键词：杞麓湖孟氏螺蛳碳同位素水体溶解无机碳

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二氟乙酰氟的制备与应用研究进展

有机氟工业 2024年第1期 34-37,58页

作者：黄挺秀于晓岗陆凤华张铭章文翔刘创中化蓝天集团有限公司浙江杭州310053 蓝启生科(浙江)新材料有限公司浙江杭州310020

二氟乙酰氟在各类杀菌剂、医药和农药等的制备过程中均有较为广泛的应用,开展二氟乙酰氟的制备与应用研究对氟化工企业发展具有重要的意义。介绍了二氟乙酰氟的多种制备方法及应用研究进展,并对各种制备方法进行了分析,认为催化氟化法... 详细信息

二氟乙酰氟在各类杀菌剂、医药和农药等的制备过程中均有较为广泛的应用,开展二氟乙酰氟的制备与应用研究对氟化工企业发展具有重要的意义。介绍了二氟乙酰氟的多种制备方法及应用研究进展,并对各种制备方法进行了分析,认为催化氟化法工艺简单,但原料不易得,催化裂解法是相对成熟的工艺,今后应着重开发高效、环保和稳定的催化剂。

关键词：二氟乙酰氟催化氟化催化裂解医药中间体农药中间体

板坯连铸机中间包塞棒断裂问题分析与改进措施

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耐火与石灰 2024年第2期49卷 43-44,58页

作者：武晓阳张文祥温巨文徐彦阳张福利唐山钢铁集团有限责任公司唐山063000

对某钢厂板坯连铸机在浇钢过程中塞棒出现的问题进行分析,发现主要为浇钢过程塞棒头掉落、塞棒棒体断裂造成的连铸机拉下,严重影响了板坯连铸机的正常生产。对塞棒断裂问题进行研究,认为塞棒的设计、施工、烘烤和使用等环节存在问题。... 详细信息

对某钢厂板坯连铸机在浇钢过程中塞棒出现的问题进行分析,发现主要为浇钢过程塞棒头掉落、塞棒棒体断裂造成的连铸机拉下,严重影响了板坯连铸机的正常生产。对塞棒断裂问题进行研究,认为塞棒的设计、施工、烘烤和使用等环节存在问题。通过改进塞棒材质,优化塞棒棒形设计,改进塞棒安装方式,改进开浇和浇钢过程中塞棒的操作等,有效改善了中间包塞棒的断裂问题,使塞棒使用趋于稳定。

关键词：中间包塞棒断裂问题分析改进措施

Oxidative coupling of alcohols and amines to an imine over Mg-Al acid-base bifunctional oxide catalysts

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Chinese Journal of Catalysis 2018年第2期39卷 309-318页

作者： Jinling Song Guiyang Yu Xi Li Xuwei Yang wenxiang zhang Wenfu Yan Gang Liu Key Laboratory of Surface and Interface Chemistry of Jilin Province College of Chemistry Jilin University Changchun 130012 Jilin China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changchun 130012 Jilin China

A series of Mg‐Al mixed oxide catalysts are prepared and introduced as efficient irreducible catalysts for the oxidative coupling of alcohols and amines to *** structure and surface properties of Mg‐Al oxides are modulated by changing the Mg/Al ratios,calcination temperature and treatment with probe *** characterization,including X‐ray diffraction,27Al magic angle spinning nuclear magnetic resonance spectroscopy,N2‐adsorption,NH3‐temperature‐programmed desorption,CO2‐temperature‐programmed desorption and X‐ray photoelectron spectroscopy are carried out to determine the physicochemical properties of these *** Mg‐Al oxides with Mg/Al=3exhibit the highest activity in the reaction,which possess a large number of surface weak basic sites and a relatively small number of weak acidic *** role of the acidic and basic sites in the reaction process is systematically investigated,and are shown to serve as adsorption and activation sites for amines and alcohols,*** the synergistic effect of these acid‐base centers,the oxidative coupling process successfully occurs on the surface of Mg‐Al mixed *** with the acidic sites,the weak basic sites play a more important role in the catalytic *** acidic sites are the catalytic centers for the benzyl alcohol activation,which control the reaction rate of the oxidative coupling reaction.

关键词： Oxidative coupling Imine synthesis Alcohol oxidation Mg‐Al mixed oxides Acid‐base catalysis

Association analysis between HFM1 variations and idiopathic azoospermia or severe oligozoospermia in Chinese Men

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Science China(Life Sciences) 2017年第3期60卷 315-318页

作者： wenxiang zhang Xiaomin Song Feng Ni Jinbao Cheng Bai-Lin Wu Hong Jiang Clinical College of PLA Affiliated Anhui Medical University Hefei 230031China Reproductive Medicine Center the 105^th hospital of PLAHefei 230031China Children's Hospital of Fudan University Institute of Biomedical ScienceShanghai Medical College of Fudan UniversityShanghaiChina 200032 Boston Children's Hospital and Harvard Medical School BostonMA 02115USA

Dear Editor,Infertility affects 10%？15%of couples trying to conceive,with male factors contributing to as many as 50%of infertile cases（Meng et al.,2015）.Azoospermia or severe oligozoospermia（oligo/azoospermia）,c... 详细信息

关键词：无精子症相关性分析男人中国

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数字孪生运维平台在某项目中的研究与应用

现代建筑电气 2024年第4期15卷 86-90页

作者：张文祥姚凌云李云祥王淑丰陕西斯科德智能科技有限公司陕西西安710018

分析了当前我国地热能在集中供暖中的利用现状,并针对系统调控中普遍存在的问题,提出基于IoT和BIM进行集中监测,并依托大数据进行优化调控的运维平台思路。然后,通过基于陕西某集团的地热能集中供暖数字孪生运维平台的案例实践,介绍了... 详细信息

分析了当前我国地热能在集中供暖中的利用现状,并针对系统调控中普遍存在的问题,提出基于IoT和BIM进行集中监测,并依托大数据进行优化调控的运维平台思路。然后,通过基于陕西某集团的地热能集中供暖数字孪生运维平台的案例实践,介绍了其策划、实施过程和应用效果,并总结了项目策划和实施中的经验。

关键词：地热能集中供热监管平台数字孪生可视化运维

Characterization and manipulation of the photosystem Ⅱ-semiconductor interfacial molecular interactions in solar-to-chemical energy conversion

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Journal of Energy Chemistry 2022年第7期31卷 437-443,I0012页

作者： Min He Wangyin Wang Zheyi Liu wenxiang zhang Jinan Li Wenming Tian Ye Zhou Yan Jin Fangjun Wang Can Li CAS Key Laboratory of Separation Sciences for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian National Laboratory for Clean EnergyDalian 116023LiaoningChina State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Semi-artificial photosynthesis interfacing catalytic protein machinery with synthetic photocatalysts exhibits great potential in solar-to-chemical energy conversion. However, characterizing and manipulating the molecular integration structure at the biotic-abiotic interface remain a challenging task. Herein,the biointerface molecular integration details of photosystem II(PSII)-semiconductor hybrids, including the PSII orientation, interfacial microdomains, and overall structure modulation, are systematically interrogated by lysine reactivity profiling mass spectrometry. We demonstrate the semiconductor surface biocompatibility is essential to the PSII self-assembly with uniform orientation and electroactive *** directional localization of PSII onto more hydrophilic Ru/Sr Ti O_(3):Rh surface exhibits less disturbance on PSII structure and electron transfer chain, beneficial to the high water splitting ***, rational modification of hydrophobic Ru_(2)S_(3)/Cd S surface with biocompatible protamine can improve the hybrid O_(2)-evolving activity 83.3%. Our results provide the mechanistic understanding to the structure–activity relationship of PSII-semiconductor hybrids and contribute to their rational design in the future.

关键词： PSII-semiconductor hybrids Biointerface molecular interaction Solar-to-chemical energy conversion Mass spectrometry Lysine reactivity profiling

HKUST-1颗粒对低浓度氙氪混合气体动态吸附分离性能的研究

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原子能科学技术 2024年第2期58卷 308-319页

作者：陈彬傅钰曹天伍岳张文祥韦冠一武山马和平西安交通大学化学工程与技术学院陕西西安710049 西北核技术研究所陕西西安710024

低浓度放射性氙(Xe)和氪(Kr)混合气的吸附分离对于其核数据的准确测量以及核设施放射性废气的净化具有重要意义。本文采用聚乙烯醇作为粘结剂制备了HKUST-1颗粒样品。HKUST-1颗粒样品的抗压测试结果表明,其具有较高的抗压强度。HKUST-1... 详细信息

低浓度放射性氙(Xe)和氪(Kr)混合气的吸附分离对于其核数据的准确测量以及核设施放射性废气的净化具有重要意义。本文采用聚乙烯醇作为粘结剂制备了HKUST-1颗粒样品。HKUST-1颗粒样品的抗压测试结果表明,其具有较高的抗压强度。HKUST-1粉末样品和颗粒样品的Xe(Kr)静态吸附数据表明,在0℃或25℃吸附温度下,HKUST-1粉末样品和颗粒样品低吸附压力下的Xe(Kr)吸附量、Xe(Kr)亨利系数以及Xe/Kr亨利选择性基本相同;造粒后颗粒样品的Xe(Kr)零点等量吸附热较造粒前减小。采用动态穿透曲线法研究了HKUST-1颗粒样品在25℃和100 kPa下分离低浓度Xe和Kr(Xe 50 ppm、Kr 50 ppm)的性能。结果表明,HKUST-1颗粒样品可实现低浓度的Xe/Kr分离,Xe穿透(c/c 0=0.02)时的Xe动态吸附量和相应的Xe/Kr动态吸附选择性随瞬时进样流量的增大而增大,Xe(Kr)饱和吸附量及相应的Xe/Kr动态吸附选择性在不同瞬时进样流量下基本保持不变。惠勒-琼斯方程对Xe穿透曲线初始部分(c/c 0≤0.02)的非线性拟合结果表明,该方程可用于预测Xe在HKUST-1颗粒吸附柱上穿透的初始阶段。

关键词： HKUST-1 造粒低浓度气体氙氪动态分离

Branched aliphatic alkanes of shell bar section in Qarhan Lake,Qaidam Basin and their paleoclimate significance

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Chinese Science Bulletin 2007年第9期52卷 1248-1256页

作者： zhang HuCai CHANG FengQin LI Bin LEI GuoLiang CHEN Yue zhang wenxiang NIU Jie FAN HongFang YANG MingSheng Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China Key Laboratory of Westem China's Environments MOE College of Earth Sciences and Environments Lanzhou University Lanzhou 730000 China

Biomarkers of paleolake deposits from Qarhan Salt Lake in Qaidam Basin,northwest China were sys-tematically analyzed and the A―C series compounds of branched aliphatic alkanes with quaternary substituted carbon atom(BAQCs) were identified. The homologous distinguished three series,A―C,were identified as 5,5-diethylalkanes,6,6-diethylalkanes and 5-butyl,5-ethylalkanes series,and their relative abundance was A > B > C. Series A and C were characterized by odd carbon numbers,whereas series B was characterized by even carbon numbers. The high values of series A corresponded with the high values of series B and C. Therefore,it can be concluded that series A,B and C possess a similar biological origin. The abundance of series A was relatively low in the lower part of the section compared with that in the upper part,implying that these series originated from bacteria and/or algae more prevalent in fresh-mesohaline water,and such kinds of bacteria and/or algae are most likely to be thermophilous species. The A25/nC25 ratio differences in the section show that such branched aliphatic alkanes can be treated as one kind of environmental change proxy for paleolake evolution and may provide important information for the climate reconstruction of the Late Pleistocene.

关键词：柴达木盆地察尔汗盐湖贝壳堤剖面侧链脂族烷古气候意义