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Science China Earth Sciences 2008年第11期51卷 1633-1645页

作者： YU JianXin LI HuiMin zhang suxin YANG FengQing FENG QingLai Key Laboratory of Biogeology and Environmental Geology of Ministry of Education China University of GeosciencesWuhan 430074China Tianjin Institute of Geology and Mineral Resources Tianjin 300170China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China

The Late Permian to Early Triassic transition represents one of the most important Phanerozoic mass extinction episodes. The cause of this event is still in debate between catastrophic and gradual mechanisms. This study uses the U-Pb method on zircons from the uppermost Permian/lowermost Triassic clay deposits at Chahe (Guizhou Province, SW China) to examine time constraints for this event. The results of both this and previous studies show that the ages of Bed 68a and 68c (the upper clay bed of the terrestrial Permian-Triassic boundary (PTB)) respectively are 252.6±2.8 and 247.5±2.8 Ma. This age (within the margin of error) almost accords with the upper clay bed (Bed 28) age of Meishan and the eruption age of Tunguss Basalt, and is so far the most accurate age obtained from terrestrial PTB. The claystone of Bed 68 was formed in the earliest Triassic. The biotic crisis occurred at nearly the same time in terrestrial and marine environments during Permian-Triassic interval; however the extinction patterns and processes are different. The extinction pattern of the terrestrial plants shows a major decline at the PTB after long-term evolution, followed by a retarded extinction of the relicts in the earliest Triassic.

关键词： terrestrial Permian-Triassic boundary floral extinction pattern U-Pb age zircons

Preparation of Mullite Whiskers and Their Enhancement Effect on Ceramic Matrix Composites

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Journal of Wuhan University of Technology(Materials Science) 2013年第3期28卷 471-475页

作者：张锦化 WU Hongdan zhang suxin Yu Jishun 侯书恩 Engineering Research Center of Nano-Materials of Mineral of Education Faculty of Material Science and Chemical Engineering China University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources

Mullite whiskers were facilely prepared by sintering kyanite at high temperature, with the addition of AlF3·3H20. The as-prepared whiskers have been characterized systematically in terms of phase composition, morphology, and structure. Results showed that the morphology and size of mullite whiskers were strongly depended on the content of AlF3·3H20 and sintering temperature. At temperatures in the range of 1 100 to 1 500 ℃ with 4 wt% addition of AlF3·3H20, the well-shaped mullite whiskers were obtained. For an instance, the mullite whiskers with 5-10 μm in length and 0.1-0.2 μm in cross-section could be formed at 1 400 ℃, with 4 wt% addition of A1F3·3H20. Moreover, results showed that the addition of mullite whiskers into ceramic matrix enhanced its fracture toughness significantly.

关键词： mullite whiskers kyanite ceramics SEM nanocrystalline materials

New Understanding of Variation Characteristics of Well Water Level in Majiagou Mine,Tangshan City,Hebei,China

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Earthquake Research in China 2020年第2期34卷 255-263页

作者： zhang suxin SHENG Yanrui DING Zhihua zhang Ziguang Hebei Earthquake Agency Shijiazhuang 050021China

Based on the well water level data in Majiagou Mine in Tangshan City since 2000,it is suggested that the water level rise from 2008-2014 is possibly associated with reduced infiltration caused by less precipitation,together with the effect of less groundwater exploitation. However,the water level rise from 1992-1998 cannot be interpreted properly if we extend the data source back to 1991. After comparing the data with long-term water level data of five wells with different hydro-geological units in Tangshan and Qinhuangdao, the study indicates that the long-term water level variation cannot be only attributed to the effect of less precipitation and the control of groundwater exploitation,but also with the influence of regional stress field *** the support of regional geological and tectonic information,combined with the comprehensive analysis of CBM data obtained from the coal field,new understandings of the dynamic characteristics of annual variation are obtained.

关键词： Majiagou Well Water level Variation characteristics Stress field

Volcanism at the Permian-Triassic Boundary in South China and Its Effects on Mass Extinction

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Acta Geologica Sinica(English Edition) 1989年第4期63卷 417-431,450-451页

作者： Yin Hongfu, Huang Siji, zhang Kexin, Yang Fengqing, Ding Meihua, Bi Xianmei and zhang suxin China University of Geosciences, Wuhan, Hubei China University of Geosciences Wuhan Hubei

This paper discusses the clayrocks widespread at the Permian-Triassic boundary, which are mostly of volcanic origin. Volcanogenetic textures, structures and minerals such as high-temperature quartz are found in clayrocks at the Permian-Triassic boundary in many places. Thousands of microspherules have been collected from the Boundary clayrocks, many of which exhibit the typical features of the process from melting to cooling and solidification. indicating that they were formed by volcanic eruption or extraterrestrial impact. Volcanic effects on the Permian-Triassic mass extinction may be reflected in conodonts, algae and ammonoids. The Boundary clayrocks are found in many Permian-Triassic sections along the coast of Tethys. Their orighin remains to be studied.

关键词： Volcanism at the Permian-Triassic Boundary in South China and Its Effects on Mass Extinction Mass

Electroacupuncture improves cognitive function in a rat model of mild traumatic brain injury by regulating the SIRT-1/PGC-1α/mitochondrial pathway

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Chinese Medical Journal 2024年第6期137卷 711-719页

作者： Bo Jin Yemei Gao Yixian Fu suxin zhang Ke zhang Yibing Su Department of Neurosurgery Beijing Jishuitan HospitalCapital Medical UniversityBeijing 100035China Department of Traditional Chinese Medicine Beijing Jishuitan HospitalCapital Medical UniversityBeijing 100035China School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing 100029China Department of Cardiology Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Department of Breast Surgical Oncology National Cancer CenterNational Clinical Research Center for CancerCancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

Background:Mild traumatic brain injury(mTBI)is a common neurological trauma that can lead to cognitive *** sirtuin-1(SIRT-1)/peroxisome proliferator-activated receptor gamma coactivator-1α(PGC-1α)pathway has been reported to have neuroprotective effects in rats with craniocerebral *** evaluated potential mechanisms underlying electroacupuncture-mediated recovery of cognitive function after mTBI,focusing on the SIRT-1/PGC-1α/mitochondrial ***:We included forty 6-week-old male Sprague-Dawley rats in this *** were randomly divided into four groups:controlled cortical impactor(CCI,n=10),sham operation(sham,n=10),electroacupuncture-treated CCI(CCI+EA,n=10),and electroacupuncture-treated sham(sham+EA,n=10)*** was performed by assigning a random number to each rat and using a random number *** mTBI rat model was established using a controllable cortical *** therapy was performed on the back of rats,by inserting acupuncture needles to the specific acupoints and setting appropriate parameters for *** evaluated spatial learning and memory functions with the Morris water maze *** performed quantitative real-time polymerase chain reaction(qRT-PCR),western blotting,adenosine triphosphate(ATP)determination,and mitochondrial respiratory chain complex I(MRCC I)determination on rat hippocampal *** analyzed SIRT-1/PGC-1α expression levels and the results of mitochondrial function assays,and compared differences between groups using bilateral Student’s ***:Compared with the sham group,SIRT-1/PGC-1α expression was downregulated in the hippocampus of CCI group(P<0.01).Although this expression was upregulated following electroacupuncture,it did not reach the levels observed in the sham group(P<0.05).Compared with the sham group,MRCC I and ATP levels in the CCI group were significantly reduced,and increased after electroacupuncture(P<0.01).In the Morris water maze,electroacupun

关键词： Electroacupuncture Cognitive impairment Sirtuin-1 Mild traumatic brain injury SIRT-1/PGC-1α/mitochondrial pathway

Theory and Method for Identifying Well Water Level Anomalies in a Groundwater Overdraft Area

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Earthquake Research in China 2007年第4期21卷 428-436页

作者： zhang suxin zhang Ziguang Ren Xiaoxia Wang Xiang Earthquake Administration of Hebei Province Shijiazhuang 050021 China zhangjiakou Seismic Station Earthquake Administration of Hebei Province Zhangjiakou 075000 China

The overexploitation of underground water leads to the continuous drawdown of groundwater levels, change of water quality and dry-up in dynamic water level observation wells. Due to land subsidence, the well pipes uplift and the observation piping systems are damaged. These environmental geology problems can present serious difficulties for the identification of earthquake anomalies by groundwater level observation. Basied on hydrogeological theories and methods, the paper analyzes the relations of the water balance state of aquifers with stress-strain conditions and the water level regime, and then discusses preliminarily the theory and method for identifying well water level anomalies in a groundwater overdraft area. The result shows that we can accurately judge the nature of the anomaly according to the diffusion character of the drawdown funnel in the well area in combination with the aforementioned theory and method and multi-year variation patterns obtained from existing data. The results of the research are helpful for distinguishing the influence of single centralized water pumping from the long-term overdraft of water on the water level, correctly recognizing water level anomalies in the groundwater overdraft area and increasing the level of earthquake analysis and prediction.

关键词： Groundwater overdraft Water level observation Anomaly recognition

能谱仪PPA分析方法的实验研究:以山西大同新生代玄武岩样品为例

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地球科学（中国地质大学学报） 2014年第9期39卷 1301-1308页

作者：张素新张毅何德涛中国地质大学地质过程与矿产资源国家重点实验室湖北武汉430074

以山西大同新生代玄武岩样品为例,利用Quanta 200扫描电镜、GENESIS能谱仪对能谱仪PPA分析方法进行了实验研究,该方法为粒度和物相自动分析方法.笔者首次把能谱仪PPA分析方法应用到地质学领域的岩石光薄片研究中,快速得出了一系列不同... 详细信息

以山西大同新生代玄武岩样品为例,利用Quanta 200扫描电镜、GENESIS能谱仪对能谱仪PPA分析方法进行了实验研究,该方法为粒度和物相自动分析方法.笔者首次把能谱仪PPA分析方法应用到地质学领域的岩石光薄片研究中,快速得出了一系列不同物相的形态学数据及化学成分分析结果:物相种类、每一种物相的颗粒数、每一个颗粒的平均直径、面积、周长、圆度、长宽比及化学成分等,并得出了不同物相在该视域所占的面积百分比及每种物相颗粒的平均直径,克服了传统光薄片粒度分析方法的所有缺点,为矿物学、岩石学及矿床学研究提供了一套非常有意义的数据.

关键词：能谱仪 PPA分析方法岩石光薄片物相粒度化学成分

Impact of Grouting and Loading of Building Construction on the Water Level of Tangshan Mine Well

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Earthquake Research in China 2014年第2期28卷 242-249页

作者： Sheng Yanrui zhang Ziguang zhang suxin Sun Dongxia Shan Lianjun Yin Baojun Earthquake Administration of Hebei Province Earthquake Administration of Tangshan City

The water level rising rate of Tangshan mine well significantly accelerated in 2010,and the ascensional range was obviously higher than that of the same period in previous *** the view of groundwater dynamics and loading effects,and based on the water pumping( pouring) water test model and semi-infinite elastic space theory model under uniform load,the effects of grouting and loading of nearby building construction on the well water level were analyzed. Results show that grouting at a distance of 200 ~ 700 m to the well,with amount of 2500m3 per day and duration of 270 d,can cause an 8 ~ 11 m rise of well water level; and loading of large-area building construction can cause about a 4m rise of well water level. Through the analysis of these factors,we find that the water level anomalous rising of Tangshan mine well was relevant to grouting and loading of the nearby building construction. This study provides a scientific basis for anomalous rising analysis of water level of Tangshan mine well.

关键词： Tangshan mine well Water level rise Uniform load theory model Pumping test model

Ordered Mesoporous Alumina for Adsorptive Removal of Low Concentration of Fluoride from Drinking Water

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Ordered Mesoporous Alumina for Adsorptive Removal of Low Con...

熔盐氯化生产TiCl_4过程中固含量控制技术研究

中国颗粒学会超微颗粒专委会2013年年会暨第八届海峡两岸超微颗粒学术研讨会

作者： Ruofang zhang Xike Tian Baodan zhang Chao Yang suxin zhang Yanxin Wang Faculty of Material Science and Chemistry China University of Geosciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences School of Environmental Studies China University of Geosciences

Two kinds of crystalline and mesoporous alumina samples were prepared using aluminium isopropoxide as precursor and P123 as template *** are labeled OMA- 800 and OMA-400 in this paper,and tested for adsorptive removal of fluoride in water. Compared with OMA-800,OMA-400 which is cost-effective combined with excellent thermal stability has narrower pore size distribution,larger surface and larger pore volume.

关键词： Adsorption Mesoporous alumina Low concentration fluorine ion Aluminium isopropoxide

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钛工业进展 2018年第5期35卷 42-46页

作者：张苏新河北钢铁集团承德分公司河北承德067102

针对熔盐氯化各工序中固含量偏高、波动大、控制困难的问题,对氯化工序全流程TiCl_4固含量展开了调研。调查结果表明,淋洗罐内固含量偏高、冷凝工序温度控制偏高造成粗TiCl_4固含量偏高和沉降过程效果不明显。针对调查结果,提出了熔盐... 详细信息

针对熔盐氯化各工序中固含量偏高、波动大、控制困难的问题,对氯化工序全流程TiCl_4固含量展开了调研。调查结果表明,淋洗罐内固含量偏高、冷凝工序温度控制偏高造成粗TiCl_4固含量偏高和沉降过程效果不明显。针对调查结果,提出了熔盐氯化炉欠氯反应技术、收尘室和淋洗系统温度控制技术及沉降控制技术等技术措施,有效降低了淋洗罐和粗TiCl_4中的固含量,使淋洗罐内的固含量稳定控制在200 g/L以内,平均值为133. 62 g/L;粗TiCl_4中的固含量控制在15 g/L以下,减小了固含物对氯化系统和成品的影响,为氯化系统的稳定运行提供了保障,为粗TiCl_4精制的产能提高奠定了基础。

关键词：熔盐氯化固含物固含量欠氯反应技术沉降控制技术