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Multivariate statistical analysis of chemical and stable isotopic data as indicative of groundwater evolution with reduced exploitation

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Geoscience Frontiers 2023年第1期14卷 133-148页

作者： Fei Liu Jingkun Zhang shiqin wang Jiawen Zou Pinna Zhen School of Water Conservancy and Hydropower Hebei University of Engineering19 Taiji RoadHandanHebei 056038China Hebei Key Laboratory of Intelligent Water Conservancy HandanHebei 056038China Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China

Groundwater resources in the North China Plain(NCP)are undergoing tremendous changes in response to the operation of groundwater exploitation reduction(GWER)*** identify groundwater evolution in this complex context,hierarchical cluster analysis(HCA)and principal component analysis(PCA)were combined to interpret an integrated dataset of stable isotopes and chemical data from four sampling campaigns in a pilot area of groundwater *** proposed a novel HCA approach integrating stable isotopes and chemical signals,which successfully partitioned the groundwater samples into the unconfined and the confined water *** isotopic evidence showed that the lateral inflow and the surface water may contribute more to groundwater recharge in this region than local modern *** unconfined water's main hydrochemical types were Na type with mixed anions,and Na-Cl-SO_(4)type,while the confined water was mainly Na-Cl and Na-SO_(4)*** processes mainly involved the dissolution/precipitation of halite,gypsum,Glauber's salt,feldspar,calcite and dolomite,as well as the cation *** results showed that water-rock interaction(i.e.,salinity-based and alkalinity-based processes)predominated the hydrochemical evolution,along with local nitrate contamination resulting from fertilizers and domestic *** GWER project regulated the natural evolution of unconfined water chemistry,and significantly reduced the unconfined water's salinity(mainly Na^(+),Mg^(2+),SO_(4)^(2-)).This may be attributed to upward leakage from low-salinity confined water at some parts of the ***,insignificant changes in the confined water's salinity reflected that the impact of GWER on the confined aquifer was *** study facilitates the groundwater classification effectively in the areas lack of geological data,and enhances the knowledge of groundwater chemical evolution in such a region where groundwater restoration is in progress,with i

关键词： Hydrochemistry Stable isotopes Groundwater evolution Groundwater exploitation reduction Hierarchical cluster analysis Principal component analysis

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Preparation of Sodium Cobalt Tetracarbonyl and Optimization of Process Conditions for Hydroesterification of Ethylene Oxide

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China Petroleum Processing & Petrochemical Technology 2018年第3期20卷 78-84页

作者： Wen Liyuan Zhang Zhanjun Chen Xiaoping wang shiqin Yu Wenli Institute of Industrial Catalysis Guangdong University of Petrochemical Technology Maoming 525000 National Quality Supervision and Inspection Center of Dangerous Chemicals (Guangdong) Maoming 525000

In this paper, sodium cobalt tetracarbonyl （NaCo（CO）4） was synthesized by using sodium dithionite and zinc powder as the reduction system and cobalt hexahydrate acetate as the precursor in the presence of methanol solvent. Methyl 3-hydroxypropionate was synthesized via hydroesterification of ethylene oxide （EO） catalyzed by NaCo（CO）4. The influencing factors on the reaction results were discussed, including the different ligands, the molar ratio of solvent and ethylene oxide, the reaction temperature, the reaction time, and the reaction pressure. An optimal catalytic system was obtained by using 3-hydroxypyridine as the ligoad under reaction conditions covering a reaction temperature 65 ℃, a reaction time of 7 h, a reaction pressure of 6 MPa, and a methoaol/EO molar ratio of 3：2. Under the optimal conditions, the conversion of ethylene oxide was equal to 97.86%, while the selectivity and yield of methyl 3-hydroxypropionate reached 88.19% and 86.30%, respectively. Finally, the reaction mechanism of hydroesterification of ethylene oxide catalyzed by NaCo（CO）4 was proposed.

关键词： sodium cobalt tetracarbonyl optimization hydroesterification reaction mechanism

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Stable isotopes of summer monsoonal precipitation in southern China and the moisture sources evidence from δ^18O signature

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Journal of Geographical Sciences 2008年第2期18卷 155-165页

作者： LIU Jianrong SONG Xianfang YUAN Guofu SUN Xiaomin LIU Xin wang Zhimin wang shiqin Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100039 China CERN Sub-center of Water Beijing 100101 China

Summer monsoons （South Asian monsoon, South China Sea monsoon and Subtropical monsoon） are prominent features of summertime climate over southern China. Dif- ferent monsoons carry different inflow moisture into China and control the temporal and spatial distributions of precipitation. Analyses of meteorological data, particularly wind, tempera- ture and pressure anomalies are traditional methods of characterizing moisture sources and transport patterns. Here, we try to utilize the evidence from stable isotopes signatures to trace summer monsoons over southern China. Based on seven CHNIP （Chinese Network of Iso- topes in Precipitation） observatory stations located in southern China, monthly composite precipitation samples have been collected and analyzed for the composition of δ^18O during July, 2005. The results indicated that the spatial distributions of δ^18O in precipitation could properly portray the moisture sources together with their transport pathways. Moreover, the amount effect, altitude effect, temperature effect and the correlation between δ^18O vs. relative humidity were discussed.

关键词： summer monsoon precipitation δ^18O vapor inflow corridors southern China

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Anomalies in Water Level Records in Yunnan Caused by the Great Indonesian Earthquakes and Their Significance

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Earthquake Research in China 2008年第4期22卷 440-447页

作者： Fu Hong Wu Chengdong Liu Qiang wang shiqin Chen Yan Earthquake Administration of Yunnan Province Kunming 650224 China

Two great earthquakes occurred in the sea northwest of Sumatra,Indonesia,on December 26,2004 and March 29,*** observation of water levels in Yunnan yielded abundant information about the two *** paper presents the water level response to the two earthquakes in Yunnan and makes a preliminary *** is observed that the large earthquake-induced abnormal water level change could be better recorded by analog recording than by digital *** large earthquake-caused water level rise or decline may be attributed to the effect of seismic waves that change the stress in tectonic units,and is correlated with the geological structure where the well is *** water level response mode in a well is totally the same for earthquakes occurring on the same fault and with the same fracture *** only difference is that the response amplitude increases with the growth of the earthquake magnitude.

关键词： Great Indonesia earthquakes Abnormal water level in Yunnan Mechanism

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云南地区地震短临预报实践

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地震 1999年第2期19卷 204-208页

作者：傅虹王世芹云南省地震局

１９９７年４～６月云南省地震局对滇西南重点监视区做了短临预报，但这期间未发生所预期的地震。而滇西南地区６级地震的背景和省内的前兆异常变化是明显的，为此，认为前兆异常是区域应力场增强的结果。异常与地震是相互伴生的兄弟关... 详细信息

１９９７年４～６月云南省地震局对滇西南重点监视区做了短临预报，但这期间未发生所预期的地震。而滇西南地区６级地震的背景和省内的前兆异常变化是明显的，为此，认为前兆异常是区域应力场增强的结果。异常与地震是相互伴生的兄弟关系，不是父子间的因果关系，是造成地震虚报的主要原因。

关键词：预报实践虚报原因云南地震预报短临预报

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Groundwater recharge under irrigated agro-ecosystems in the North China Plain: From a critical zone perspective

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Journal of Geographical Sciences 2019年第6期29卷 877-890页

作者： MIN Leilei QI Yongqing SHEN Yanjun wang Ping wang shiqin LIU Meiying Key Laboratory of Agricultural Water Resources Hebei Key Laboratory of Water-Saving AgricultureCenter for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyCAS Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchCAS University of Chinese Academy of Sciences

From a critical zone perspective, the present paper aims to present the magnitude of groundwater recharge under different agricultural land-use types, reveal the process of water and solute transport in thick vadose zone, evaluate the "time lag" effect of recharge, and underscore the role of thickening vadose zone in recharge. The results indicated that different agricultural land-use types need to be further considered in recharge rate estimate. Under the typical irrigation condition in the piedmont plain, the recharge rate under flood irrigated winter wheat and summer maize(W/M_F), maize(M), non-cultivation(NC), native vegetation(NV), vegetables(V), and orchards(O) is 206.4, 149.7, 194.1, 46.4, 320.0, and 48.6 mm/yr, respectively. In the central plain, the value under W/M_F, M, NC, V, and cotton(C) is 92.8, 50.8, 85.0, 255.5, and 26.5 mm/yr, respectively. Soil water residence time(several years) and groundwater level response time(several months) should be distinguished to further understand the processes of groundwater recharge, because the soil water displacement velocities range from 0.2 to 2.2 m/yr while the rate of wetting front propagation is approximately 47 m/yr in the piedmont plain. The thickening vadose zone would prolong residence time of soil water and contaminant, which could postpone the time of or alleviate groundwater pollution, but have no significant influence on the magnitude of recharge in a long time scale. Recharge coefficient based on shorter time span(e.g. 2 or 3 years) should be used with caution as a parameter for groundwater resources evaluation, because it varies with total water input and target soil depth. Uncertainties in evapotranspiration and other water balance components should be evaluated in recharge estimation and the impact of land-use types on recharge should be emphasized. The critical zone science would greatly improve the understanding of groundwater recharge processes. The results of the present study will be helpful in

关键词： groundwater recharge critical zone irrigated agro-ecosystems North China Plain

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定向机信息处理及控制

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光电子．激光 1998年第5期9卷 401-403页

作者： wang shiqin (Department of Electrical Engineering,Tianjin University,Tianjin 300072) 天津大学电子工程系

本文设计并研制了定向机信息处理及控制系统。该系统使用ＭＳＣ－５１单片机作为主处理器件并实现了飞机方位的检测、计算、显示以及系统的校准。

关键词：定向机方位检测校准自检飞机导航设备

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饲粮蛋氨酸水平对羔羊肝脏及血清中蛋氨酸循环代谢相关指标的影响

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动物营养学报 2019年第1期31卷 188-197页

作者：王杰崔凯王世琴刁其玉张乃锋中国农业科学院饲料研究所农业部饲料生物技术重点开放实验室北京100081

本试验旨在研究饲粮蛋氨酸水平对羔羊肝脏及血清中蛋氨酸循环代谢相关指标的影响。利用配对试验设计方法,选取平均体重为(4.93±0.20) kg的12对7日龄断母乳湖羊双胞胎公羔,每对双胞胎羔羊分别分到2组中,试验分2个阶段进行。第1阶段(8～5... 详细信息

本试验旨在研究饲粮蛋氨酸水平对羔羊肝脏及血清中蛋氨酸循环代谢相关指标的影响。利用配对试验设计方法,选取平均体重为(4.93±0.20) kg的12对7日龄断母乳湖羊双胞胎公羔,每对双胞胎羔羊分别分到2组中,试验分2个阶段进行。第1阶段(8～56日龄),2组羔羊分别补充[饲喂基础代乳粉+0.70%蛋氨酸、基础开食料+0.40%蛋氨酸,对照组(CON组)]和限制蛋氨酸[饲喂基础代乳粉、基础开食料,低蛋氨酸组(LM组)]。第2阶段(57～84日龄),2组羔羊停止饲喂基础代乳粉,继续饲喂相同的补充蛋氨酸饲粮(基础开食料+0.40%蛋氨酸)。在56和84日龄,各选取6对双胞胎羔羊进行屠宰,采集血液和分离肝脏并液氮保存用于测定蛋氨酸循环代谢相关指标。结果表明:1) 56日龄时,LM组羔羊肝脏中蛋氨酸含量显著高于CON组(P0.05); 84日龄时,LM组羔羊肝脏中BHMT、甲硫氨酸腺苷转移酶(MAT)和甘氨酸-N-甲基转移酶(GNMT)活性均显著低于CON组(P0.05)。由此可见,饲粮中低蛋氨酸水平虽显著降低了羔羊肝脏中BHMT活性及血清中蛋氨酸和SAM含量,却激发了肝脏中蛋氨酸的生成,同时显著影响到肝脏SAM/SAH值,使体内甲基供体水平下降,影响羔羊正常甲基代谢;恢复饲粮蛋氨酸水平后,肝脏及血清中蛋氨酸循环代谢相关指标等表观性状未能完全随蛋氨酸的补充而恢复。

关键词：羔羊蛋氨酸蛋氨酸循环甲基代谢

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高师学前藏汉双语教育专业美术课教学思考

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四川文理学院学报 2018年第3期28卷 103-105页

作者：王世琴阿坝师范学院美术学院四川汶川623002

高师学前藏汉双语教育人才培养关系藏区社会进步、经济繁荣和社会稳定的大局,是直接涉及藏区民生问题的大事。如何进一步改进该专业人才培养过程中存在的不足,优化人才培养方案,提高人才培养质量是一个系统工程。其中美术课程教学成效... 详细信息

高师学前藏汉双语教育人才培养关系藏区社会进步、经济繁荣和社会稳定的大局,是直接涉及藏区民生问题的大事。如何进一步改进该专业人才培养过程中存在的不足,优化人才培养方案,提高人才培养质量是一个系统工程。其中美术课程教学成效最大化,是我们优化课程结构、提高人才培养质量的一个不可或缺的部分。

关键词：学前藏汉双语教育美术课思考

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多孔介质表面化学异质性对胶体运移的影响

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环境科学学报 2017年第9期37卷 3498-3504页

作者：袁瑞强郭威王鹏王仕琴山西大学环境与资源学院太原030006 山西大学资源与环境工程研究所太原030006 江西师范大学鄱阳湖湿地与流域研究教育部重点实验室南昌330022 中国科学院遗传所农业资源研究中心石家庄050021

研究胶体在饱和多孔介质中的迁移行为在污染物迁移、环境修复等领域具有重要意义.本文通过对比胶体在未酸洗和酸洗过的玻璃珠中的迁移行为来探究多孔介质表面异质性对胶体迁移的影响,并通过扩展DLVO理论来计算每一组中胶体与多孔介质的... 详细信息

研究胶体在饱和多孔介质中的迁移行为在污染物迁移、环境修复等领域具有重要意义.本文通过对比胶体在未酸洗和酸洗过的玻璃珠中的迁移行为来探究多孔介质表面异质性对胶体迁移的影响,并通过扩展DLVO理论来计算每一组中胶体与多孔介质的相互作用能.结果表明,不论在有利环境还是在不利环境下,多孔介质表面的化学杂质均会提高胶体的吸附能力,这主要归因于胶体在初级势阱中的吸附.不利环境下,多孔介质表面的化学杂质能够将不利环境转化为有利环境,而在有利环境下,化学杂质的存在可能提高胶体的单一拦截效率(η_0).此外,研究发现,高pH溶液仍然能使胶体从多孔介质表面解吸下来,并且沥滤作用仍被低估.本研究对化学杂质在胶体迁移过程中所扮演的角色有了进一步的认识,可为胶体迁移行为研究提供实验依据.

关键词：胶体迁移多孔介质化学异质性

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