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基于气相色谱法的地下水质中有机污染物测定方法

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化学与粘合 2024年第1期46卷 100-105页

作者：许玉坤禹海清张璐河北省地质环境监测院河北石家庄050000

水质环境中的有机污染物严重危害人类生存,影响人体健康,为提高污染物的检测精度,研究基于气相色谱法的地下水质中有机污染物测定方法。以便携式工作站集成水样采集单元,采集定量时间内的地下水样本。通过地下水质中有机污染物定性原理... 详细信息

水质环境中的有机污染物严重危害人类生存,影响人体健康,为提高污染物的检测精度,研究基于气相色谱法的地下水质中有机污染物测定方法。以便携式工作站集成水样采集单元,采集定量时间内的地下水样本。通过地下水质中有机污染物定性原理,选择待测试仪器,并针对测试项目制定仪器操作条件。设计有机污染物的测定方法,筛选有机污染物风险因子,设定污染物常用理化参数,预测有害物质的含量。采用加法或乘法运算准则,对独立存在的因子进行加权处理,描述有机污染物在地下水中迁移过程,最后通过气相色谱法实现地下水质中的有机污染物测定。实验结果表明:分别以旋转蒸发温度为35℃和2 mm氦吹流速为检出回收标准,验证污染物测定的精准度。当6种污染物浓度设定为低标10μg/L和高标20μg/L时,方法测定平均值的标准偏差为0.15和0.2,说明该方法的测定结果精度较高。

关键词：气相色谱法地下水质有机污染物污染物迁移风险因子

Highly efficient pH-universal hydrogen evolution reaction catalyzed by rapidly reconstructed bimetallic cobalt-molybdenum alloy cuboids arrays

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Nano Research 2024年第8期17卷 6977-6983页

作者： Daolian Liu Zihao Wang Yan Zhang haiqing Zhou Yong Zhang Dongyang Li Fang yu Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Key Laboratory for Matter Microstructure and Function of Hunan ProvinceDepartment of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China State Key Laboratory of Marine Resource Utilization in South China Sea and Department of Materials Science and EngineeringHainan UniversityHaikou 570228China Institute of Interdisciplinary Studies Hunan Normal UniversityChangsha 410081China

Given the inherent potential of seawater,industrial wastewater,and residential water as inherent feedstocks for hydrogen production through water electrolysis,there is a critical demand for the exploration of robust and stable hydrogen-evolving catalysts that can operate effectively across a diverse range of pH ***,the pursuit of hydrogen-evolving electrocatalysts that demonstrate both good stability and high efficiency over a wide pH range remains a formidable *** we report the rational design and synthesis of an outstanding nanoporous hybrid electrocatalyst consisting of intermetallic cobalt-molybdenum alloy particles anchoring on MoO2 cuboid arrays,which demands very low overpotentials of 72,123 and 134 mV to deliver a current density of−100 mA·cm^(−2)for hydrogen evolution reaction under alkaline,neutral and acidic conditions,*** catalytic activities are superior to most non-precious-metal-based catalysts documented in the literatures,and are even comparable to noble metal *** particular,this alloy electrocatalyst exhibits excellent stability at 50 or 300 mA·cm^(−2)without obvious activity degradation,which is further supported by the undetectable changes in the surface chemical valence states on the basis of in-situ X-ray photoelectron spectroscopic *** study provides an innovative strategy for the design and synthesis of effective non-noble intermetallic catalysts for pH-universal hydrogen evolution over a wide pH range.

关键词： electrocatalyst hydrogen evolution reaction pH-universal non-noble water splitting

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甘孜州林业碳汇资源分析及开发策略

现代农业科技 2024年第16期 76-80,95页

作者：李元会吴富雨刘燕云余海清文嫱刘韩甘孜藏族自治州林业科学研究所四川甘孜626001

林业碳汇是全球公认的经济且能有效减缓温室效应的重要途径,大力发展林业碳汇有助于实现我国“双碳”目标,推动甘孜州林草工作高质量发展。本文基于林业碳汇相关方法学,以甘孜州森林资源数据为对象,预测了未来30年的人工造林、森林经营... 详细信息

林业碳汇是全球公认的经济且能有效减缓温室效应的重要途径,大力发展林业碳汇有助于实现我国“双碳”目标,推动甘孜州林草工作高质量发展。本文基于林业碳汇相关方法学,以甘孜州森林资源数据为对象,预测了未来30年的人工造林、森林经营碳汇量,结果表明,甘孜州人工造林项目2.89万hm^(2),可产生人工造林碳汇量203.24万t CO_(2)e;森林经营项目23.70万hm^(2),可产生森林经营碳汇量1 302.42万t CO_(2)e;造林绿化空间24.34万hm^(2),预测人工造林碳汇潜力1 539.78万t CO_(2)e;幼龄林、中龄林、近熟林存量162.76万hm^(2),预测森林经营碳汇潜力9 443.73万t CO_(2)e。基于测算结果,分析了甘孜州林业碳汇发展中的问题,提出了开发策略,以期为发展林业碳汇、制定开发策略和管理办法提供参考。

关键词：林业碳汇林业资源碳汇潜力问题开发策略四川甘孜

Anchoring Ru clusters to highly defective N-doped carbon nanotubes via a thermal-shock strategy for stable industrial hydrogen evolution

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Nano Research 2024年第6期17卷 5261-5269页

作者： Zhiming Li Xinyu Li haiqing Ma Chenliang Ye Hongan yu Long Nie Meng Zheng Jin Wang College of Materials Science and Engineering Shenzhen UniversityShenzhen 518060China School of Chemistry and Materials Science Anhui Normal UniversityWuhu 241002China Department of Power Engineering North China Electric Power UniversityBaoding 071003China

Non-Pt or low-Pt catalysts capable for stable generation of hydrogen via water electrolysis at an industrial level of current density are highly *** of strong metal-support connection is beneficial to improve the performance stability of *** we employed highly defective N-doped carbon nanotubes(d-N-CNT)as the support to achieve uniform and firm anchoring of Ru clusters(~1.9 nm)via a thermal-shock *** as-prepared Ru/d-N-CNT catalyst shows excellent catalytic activity for hydrogen evolution reaction(HER)in alkaline media and requires an overpotential(ƞ)of 12 mV at 10 mA·cm^(−2)and 116 mV at 200 mA·cm^(−2)with a Ru loading of 0.025 mg·cm^(−2).Impressively,Ru/d-N-CNT presents robust stability for HER at both low current density(stable for at least 1000 h at 10 mA·cm^(−2))and the industrial level of current density(stable for at least 100 h at 1000 mA·cm^(−2)),remarkably outperforming commercial Pt/C and Ru/*** highly defective nature of the N-CNT support endowed the as-prepared Ru/d-N-CNT catalyst with strong metal-support adhesion that efficiently suppressed agglomeration as well as obscission of Ru ***,the rich defects increased the surface energy of the N-CNT support and resulted in improved hydrophilicity as evidenced by the liquid contact angle measurement and the bubble evolution process,which also played an important role in stabilizing the HER performance especially at large current density.

关键词： thermal-shock method hydrogen evolution reaction large-current-density Ru cluster

贡嘎山国家级自然保护区多鳞杜鹃群落结构及其多样性特征

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四川林业科技 2024年第3期45卷 50-55页

作者：夏苗余海清马文宝董廷发帅伟姜欣华刘燕云李元会甘孜藏族自治州林业科学研究所四川康定626001 四川省林业科学研究院森林和湿地生态恢复与保育四川重点实验室四川成都610081 西华师范大学四川南充637009

为保护中国特有种多鳞杜鹃,调查了多鳞杜鹃群落的生境状况、物种组成、生活组成、结构特点和物种多样性分析。结果表明,多鳞杜鹃分布范围广,分布在海拔1 800 m~3 200 m区域,为林内生态幅度较宽的植被类型。三个不同海拔梯度多鳞杜鹃群... 详细信息

为保护中国特有种多鳞杜鹃,调查了多鳞杜鹃群落的生境状况、物种组成、生活组成、结构特点和物种多样性分析。结果表明,多鳞杜鹃分布范围广,分布在海拔1 800 m~3 200 m区域,为林内生态幅度较宽的植被类型。三个不同海拔梯度多鳞杜鹃群落共分布22科、35属、47种植物。多鳞杜鹃有多种生活型植物组成,其中以高位芽植物和地上芽植物为主,从垂直结构看,多鳞杜鹃群落分布有乔、灌、草层,分层现象明显,多鳞杜鹃和丰实箭竹为灌木层优势种。多鳞杜鹃群落以草本层的生物多样性最高,在高海拔区域乔木层的优势种明显随海拔降低呈降低趋势。不同海拔梯度下多鳞杜鹃群落各项多样性指数表明多鳞杜鹃群落各层次的物种丰富度指数、多样性指数、优势度指数、均匀度指数均表现出草本层>灌木层>乔木层一致性特征。物种多样性与物种丰富度成正比,物种多样性越高代表群落稳定性越好。

关键词：多鳞杜鹃贡嘎山群落特征物种多样性

Adenine: an important drug scaffold for the design of antiviral agents

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Acta Pharmaceutica Sinica B 2015年第5期5卷 431-441页

作者： Changyuan Wang Zhendong Song haiqing yu Kexin Liu Xiaodong Ma College of Pharmacy Dalian Medical University

Adenine derivatives, in particular the scaffold bearing the acyclic nucleoside phosphonates(ANPS), possess signi fi cant antiviral and cytostatic activity. Till now, several effective adenine derivatives have been marketed for the treatment of HIV, HBV, CMV and other virus-infected diseases. These compounds are represented by tenofovir(PMPA), a medicine for both HIV and HBV, and adefovir as an anti-HBV agent. More than this, other analogs, such as GS9148, GS9131, and GS7340, are also wellknown anti-viral agents that have been progressed to the clinical studies for their excellent activity. In general, the structures of these compounds include an adenine nucleobase linked to a phosphonate side chain. Considerable structural modi fi cations on the scaffold itself and the peripheral sections were *** structure-activity relationships(SARs) of this skeleton will provide valuable clues to identify more effective adenine derivatives as antiviral drugs. Here, we systematically summarized the SARs of the adenine derivatives, and gave important information for further optimizing this template.

关键词： Antiviral Structure–activity relationship Adenine Acyclic nucleoside phosphonates Scaffold

Dynamic Brain Responses Modulated by Precise Timing Prediction in an Opposing Process

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Neuroscience Bulletin 2021年第1期37卷 70-80页

作者： Minpeng Xu Jiayuan Meng haiqing yu Tzyy-Ping Jung Dong Ming College of Precision Instruments and Optoelectronics Engineering Tianjin UniversityTianjin 300072China Academy of Medical Engineering and Translational Medicine Tianjin UniversityTianjin 300072China Swartz Center for Computational Neuroscience University of CaliforniaSan DiegoCA 92093USA

The brain function of prediction is fundamental for human beings to shape perceptions efficiently and successively. Through decades of effort, a valuable brain activation map has been obtained for prediction. However,much less is known about how the brain manages the prediction process over time using traditional neuropsychological paradigms. Here, we implemented an innovative paradigm for timing prediction to precisely study the temporal dynamics of neural oscillations. In the experiment recruiting 45 participants, expectation suppression was found for the overall electroencephalographic activity,consistent with previous hemodynamic studies. Notably,we found that N1 was positively associated with predictability while N2 showed a reversed relation to predictability. Furthermore, the matching prediction had a similar profile with no timing prediction, both showing an almost saturated N1 and an absence of N2. The results indicate that the N1 process showed a ‘sharpening' effect for predictable inputs, while the N2 process showed a‘dampening' effect. Therefore, these two paradoxical neural effects of prediction, which have provoked wide confusion in accounting for expectation suppression,actually co-exist in the procedure of timing prediction but work in separate time windows. These findings strongly support a recently-proposed opposing process theory.

关键词： Expectation suppression Predictive coding Event-related potentials Timing prediction

Optimization of environmental variables in habitat suitability modeling for mantis shrimp Oratosquilla oratoria in the Haizhou Bay and adjacent waters

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Acta Oceanologica Sinica 2020年第6期39卷 36-47页

作者： yunlei Zhang Huaming yu haiqing yu Binduo Xu Chongliang Zhang Yiping Ren Ying Xue Lili Xu College of Fisheries Ocean University of ChinaQingdao 266003China Laboratory for Marine Fisheries Science and Food Production Processes Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China Institute of Oceanology Chinese Academy of SciencesQingdao 266071China

Habitat suitability index(HSI)models have been widely used to analyze the relationship between species abundance and environmental factors,and ultimately inform management of marine *** response of species abundance to each environmental variable is different and habitat requirements may change over life history stages and ***,it is necessary to determine the optimal combination of environmental variables in HSI *** this study,generalized additive models(GAMs)were used to determine which environmental variables to be included in the HSI *** variables were retained and weighted in the HSI model according to their relative contribution(%)to the total deviation explained by the boosted regression tree(BRT).The HSI models were applied to evaluate the habitat suitability of mantis shrimp Oratosquilla oratoria in the Haizhou Bay and adjacent areas in 2011 and 2013–*** and seasonal variations in HSI models of mantis shrimp were also *** the four models(non-optimized model,BRT informed HSI model,GAM informed HSI model,and both BRT and GAM informed HSI model),both BRT and GAM informed HSI model showed the best *** environmental variables(bottom temperature,depth,distance offshore and sediment type)were selected in the HSI models for four groups(spring-juvenile,spring-adult,falljuvenile and fall-adult)of mantis *** distribution of habitat suitability showed similar patterns between juveniles and adults,but obvious seasonal variations were *** study suggests that the process of optimizing environmental variables in HSI models improves the performance of HSI models,and this optimization strategy could be extended to other marine organisms to enhance the understanding of the habitat suitability of target species.

关键词： habitat suitability index mantis shrimp generalized additive model boosted regression tree Haizhou Bay

坚定行进在推动人类发展进步的道路上——2022年外国共产党的新发展与新动向

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当代世界 2023年第1期 59-65页

作者：于海青中国社会科学院大学中国社会科学院马克思主义研究院

2022年,外国共产党逐渐步入一个新的发展周期。多国共产党隆重纪念十月革命105周年、苏联成立100周年等系列活动。多国共产党参加国内各层级选举,但支持率普遍下滑,整体成绩惨淡。多国共产党召开全国代表大会或中央全会,总结阶段性发展... 详细信息

2022年,外国共产党逐渐步入一个新的发展周期。多国共产党隆重纪念十月革命105周年、苏联成立100周年等系列活动。多国共产党参加国内各层级选举,但支持率普遍下滑,整体成绩惨淡。多国共产党召开全国代表大会或中央全会,总结阶段性发展工作,为未来发展确定方向和目标。外国共产党积极加强联系与沟通,谋求共识与合作,但在一些重大理论和实践问题上的分歧也导致相关矛盾冲突凸显。外国共产党继续坚持不懈反对霸权主义,维护和平,捍卫社会公平正义,推动人类社会发展与进步。面向未来,各国共产党唯有相互尊重、求同存异,才能最大程度地弥合分歧、实现协作,推动世界社会主义不断走向振兴。

关键词：外国共产党国际共产主义世界社会主义工人党