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海南岛东海岸官塘地区地热水水化学特征及其循环演化过程识别

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地球科学 2024年第3期49卷 952-964页

作者：张彦鹏黎清华余绍文中国地质调查局武汉地质调查中心湖北武汉430205

地热水资源的形成与演化过程认识是区域地热资源科学合理开发利用的重要基础.运用水化学及同位素分析方法,结合区域地质构造特征,系统揭示了海南东海岸官塘地区地热水水化学特征、地热储温度以及补给来源,构建了官塘地区地热水循环演化... 详细信息

地热水资源的形成与演化过程认识是区域地热资源科学合理开发利用的重要基础.运用水化学及同位素分析方法,结合区域地质构造特征,系统揭示了海南东海岸官塘地区地热水水化学特征、地热储温度以及补给来源,构建了官塘地区地热水循环演化概念模型.研究结果表明:该区地热水水化学类型主要为HCO_(3)·SO_(4)-Na型,其组分主要来源于硅酸盐矿物溶解及深部CO_(2)等气体;地热水主要受到大气降水补给,补给海拔约为1122.2~1569.4 m,并且地热水上升过程中与浅部地下水之间存在较为显著的混合作用.在考虑混合和蒸汽损失的条件下,深部地热水与冷水混合前蒸汽损失的质量百分比约为18.2%~25.2%,地热水温度为190.4~217.8℃,冷水混合比例可达到66.8%~80.8%.该地区地热水开发程度逐年提高,导致地热水水位大幅下降,使得浅部冷水补给量增大,这可能是造成该地区开采地热水温度下降的关键影响因素.

关键词：官塘地热田地热水资源水文地球化学地热水补给来源热储温度水文地质

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鄱阳湖湖滨多宝沙山成因机制

吉林大学学报（地球科学版） 2024年第4期54卷 1383-1395页

作者：徐俊杰陈松刘广宁刘道涵余绍文中国地质调查局武汉地质调查中心(中南地质科技创新中心) 武汉430205

鄱阳湖地区属于亚热带季风性湿润气候带,湖滨却多处发育沙漠。多宝沙山是湖滨面积最大的沙漠,给当地环境造成了非常严重的危害。前人多认为多宝沙山是风成的;然而,沙山多处沿岸露头的地层层理均表现为水成特征。为进一步明确多宝沙山成... 详细信息

鄱阳湖地区属于亚热带季风性湿润气候带,湖滨却多处发育沙漠。多宝沙山是湖滨面积最大的沙漠,给当地环境造成了非常严重的危害。前人多认为多宝沙山是风成的;然而,沙山多处沿岸露头的地层层理均表现为水成特征。为进一步明确多宝沙山成因,本研究进行了物探(高密度电阻率法和瞬变电磁法)和野外地质露头调查,发现第四系除风成特征外,还具有水成的厚度分布及层序地层特征。本研究认为多宝沙山是风力搬运和水下沉积共同作用的结果,其形成与湖平面多次起伏、彭蠡泽南扩、湖底平坦的地形、三角洲快速沉积、断块差异运动、强劲的冬季风等多重因素在时间和空间上的耦合相关。多宝沙山形成于全新世时期,位于古赣江三角洲前缘亚相,后期发生构造抬升,多宝沙山被强风改造,风沙覆盖了除西山、笔架山之外的古构造高地,最终形成了现今的多宝沙山。

关键词：南方沙漠鄱阳湖多宝沙山高密度电阻率法瞬变电磁法成因机制

A New Expression of the Hermitian Solutions to a System of Matrix Equations with Applications

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Algebra Colloquium 2016年第1期23卷 167-180页

作者： Guangjing Song shaowen yu Ming Chen School of Mathematics and Information Sciences Weifang University Weifang Shandong 261061 China Department of Mathematics East China University of Science and Technology Shanghai 200237 China College of Mathematics Physics and Information Engineering Jiaxing University Jiaxing Zhejiang 314000 China

In this paper, a new necessary and sufficient condition for the existence of a Hermitian solution as well as a new expression of the general Hermitian solution to the system of matrix equations A1X = C1 and A3XB3 = C3 are derived. The max-min ranks and inertias of these Hermitian solutions with some interesting applications are shown. In particular, the max-min ranks and inertias of the Hermitian part of the general solution to this system are presented.

关键词： matrix equations linear matrix expression generalized inverse inertias

江西浒坑-分宜地区1:5万水系沉积物地球化学特征研究

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东华理工大学学报（自然科学版） 2024年第3期47卷 246-257页

作者：符海明徐喆吴正昌余少文贺彬樊蓉江西省地质调查勘查院基础地质调查所江西南昌330030 江西省地质局第一地质大队江西南昌330030

江西浒坑分宜地区属于武功山矿集区的一部分,是华南重要的稀有金属成矿区。为实现新一轮找矿突破,根据1∶5万水系沉积物地球化学测量成果,对元素地球化学特征进行了分析,利用元素原始数据异常、衬值异常、比值异常等方法分别圈定异常并... 详细信息

江西浒坑分宜地区属于武功山矿集区的一部分,是华南重要的稀有金属成矿区。为实现新一轮找矿突破,根据1∶5万水系沉积物地球化学测量成果,对元素地球化学特征进行了分析,利用元素原始数据异常、衬值异常、比值异常等方法分别圈定异常并进行对比。结果表明,衬值异常法对稀有金属找矿具有良好的指示意义。稀有金属成矿元素Ta、Nb、Li、Rb、Cs、Be与W、Sn关系密切,局部存在W、Sn形成的异常更强、范围更大,而Ta、Nb等稀有金属元素异常偏弱的情况,可能存在“上钨锡、下稀有金属”的元素垂向分带现象,建议开展“就钨找稀有金属”工作。

关键词：水系沉积物测量地球化学化探异常稀有金属矿床江西

An equivalence canonical form of a matrix triplet over an arbitrary division ring with applications

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Science China Mathematics 2011年第5期54卷 907-924页

作者： WANG QingWen van der WOUDE J. W. yu shaowen Department of Mathematics Shanghai University Shanghai 200444 China Faculty of Electrical Engineering Mathematics and Computer ScienceDelft University of Technology Mekelweg 4 2628 CD Delft The Netherlands Department of Mathematics East China University of Science and Technology Shanghai 200237 China

We in this paper give a decomposition concerning the general matrix triplet over an arbitrary divisionring F with the same row or column numbers. We also design a practical algorithm for the decomposition of thematrix triplet. As applications, we present necessary and suficient conditions for the existence of the generalsolutions to the system of matrix equations DXA = C1, EXB = C2, F XC = C3 and the matrix equation AXD + BY E + CZF = Gover F. We give the expressions of the general solutions to the system and the matrix equation when thesolvability conditions are satisfied. Moreover, we present numerical examples to illustrate the results of thispaper. We also mention the other applications of the equivalence canonical form, for instance, for the compressionof color images.

关键词： division ring linear matrix equation equivalence canonical form of a matrix triplet decomposition

三氯蔗糖ESI正模式中加钠离子[M+Na]^(+)的特征碎片结构分析研究

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广东化工 2024年第18期51卷 10-13页

作者：池少铃陈子凡林锦锋余少文张俊华河源市药品检验所广东河源517000 河源市食品检验所广东河源517000 广东省药品检验所广东广州510663 国家药监局药用辅料质量控制与评价重点实验室广东广州510663 广州白云山光华制药股份有限公司广东广州510000

分析三氯蔗糖在ESI正模式中[M+Na]^(+)的裂解过程,得出裂解路径和产物分子,为建立基于特征碎片结构快速筛查数据库提供参考。通过优化程序及调整流动相等参数,分析三氯蔗糖加钠的前体离子的谱图规律,结合分析特征产物离子的碰撞能量、强... 详细信息

分析三氯蔗糖在ESI正模式中[M+Na]^(+)的裂解过程,得出裂解路径和产物分子,为建立基于特征碎片结构快速筛查数据库提供参考。通过优化程序及调整流动相等参数,分析三氯蔗糖加钠的前体离子的谱图规律,结合分析特征产物离子的碰撞能量、强度,以及特征中性丢失,确定特征碎片,推测可能裂解路径,最后通过对自然界氯同位素丰度比的计算,验证了所提出的裂解途径和分子式的有效性。在Q1质谱图中主要生成[M+Na]+加钠离子,Q2质谱图中主要生成239 m/z、221 m/z两个产物离子及其他2个次主要离子,而且这两个离子相对丰度高、稳定性好,结合氯同位素在自然界的丰度比进行计算,验证了该推导裂解路径和分子式的存在合理性。结论为三氯蔗糖在ESI正模式下的应用提供了参考,为三氯蔗糖质谱碎裂模式的分析奠定了理论基础。

关键词：三氯蔗糖正电离喷雾模式加钠离子裂解途径

Efficient overall photosynthesis of H_(2)O_(2) by the BTz@Mn_(0.2)Cd_(0.8)S S-scheme heterojunction

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Science China Chemistry 2024年第6期67卷 1953-1960页

作者： Zhongyue Chen Sijie Wan Bei Cheng Wang Wang Yao Xiang Jiaguo yu shaowen Cao State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China Hubei Technology Innovation Center for Advanced Composites Wuhan University of TechnologyWuhan430070China Hospital of Wuhan University of Technology Wuhan University of TechnologyWuhan430070China Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan430074China

The photosynthesis of hydrogen peroxide(H_(2)O_(2))through the selective 2e^(-)oxygen reduction reaction(ORR)from O_(2)and H_(2)O stands out as an environmentally sustainable and cost-effective method for generating this essential ***,the widespread application of most photocatalysts is impeded by their reliance on sacrificial *** this context,we present a noteworthy advancement in the form of a step-scheme(S-scheme)heterojunction involving a donor-acceptor(D-A)-conjugated polymer and manganese cadmium sulfide(BTz@MCS).This innovative configuration enables efficient photocatalytic H_(2)O_(2)production within a non-sacrificial system,showcasing an impressive H_(2)O_(2)yield of 5,368μmol g^(-1)h^(-1)and an apparent quantum yield of 4.5%at 420 *** insights gained from in-situ irradiated X-ray photoelectron spectroscopy(ISIXPS),in-situ diffuse reflectance infrared Fourier transformations spectroscopy(DRIFTS),and density function calculations(DFT),it is revealed that the sp^(2)C between thiazole-thiazole rings at the BTz and the concentrated holes at the MCS function as spatially separated redox *** centers catalyze the selective 2e^(-)ORR and 4e^(-)water oxidation reaction(WOR)*** O_(2)generated from the WOR is subsequently utilized by the ORR cycle,enabling the overall photosynthesis of H_(2)O_(2)with accelerated total reaction ***,the high photocatalytic performance of the developed catalyst is attributed to well-designed S-scheme heterojunctions with tuned band *** spatially separated redox centers and effective transfer of photogenerated charge carriers facilitated by the internal electric field significantly enhance reaction *** study introduces a promising avenue for photocatalytic H_(2)O_(2)production without sacrificial agents,providing valuable insights into the underlying mechanisms in S-scheme heterojunctions.

关键词： hydrogen peroxide non-sacrificial redox centers S-scheme heterojunction

Truncation of a mannanase from Trichoderma harzianum improves its enzymatic properties and expression efficiency in Trichoderma reesei

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Truncation of a mannanase from Trichoderma harzianum improve...

The Ninth National Symposium on Enzyme Engineering

作者： Juan Wang Desheng Zeng Gang Liu shaowen Wang shaowen yu College of Life Science Shenzhen Key Laboratory of Microbial Genetic EngineeringShenzhen University

Mannan is a major hemi-cellulose that is present in the cell walls and in the seeds of ***β-1,4-mannanases（β-mannanases,EC 3.***.1.78）can catalyze the hydrolysis of structurally different *** on sequence similarities,these enzymes are mainly grouped into glycoside hydrolase families 5 and *** are ubiquitous in nature and a vast variety of bacteria,actinomycetes,yeasts and filamentous fungi are known to be mannan *** are many applications for mannanases in industrial *** obtain high expression efficiency of a mannanase gene,ThMan5A,cloned from Trichoderma harzianum MGQ2,both the full-length gene and a truncated gene（ThMan5AΔCBM）that contains only the catalytic domain were expressed in Trichoderma reesei QM9414 using the strong constitutive promoter of the gene encoding pyruvate decarboxylase（pdc）,and purified to homogeneity,*** found that truncation of the gene improved its expression efficiency as well as the enzymatic properties of the encoded *** recombinant strain expressing ThMan5AΔCBM produced 2460±45.1U/mL of mannanase activity in the culture supematant;2.3-fold higher than when expressing the full-length ThMan5A *** addition,the trtmcated mannanase had superior thermostability compared with the full length enzyme and retained 100%of its activity after incubation at 60℃C for 48 *** results clearly show that the truncated ThMan5A enzyme exhibited improved characteristics both in expression efficiency and in its thermal *** characteristics suggest that ThMan5AΔCBM has potential applications in the food,feed,paper and pulp industries.

关键词： Mannanase Trichoderma harzianum Trichoderma reesei carbohydrate-binding module thermostability

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企业间协同创新惰性及解决对策

科技进步与对策 2013年第10期30卷 84-87页

作者：肖鹏余少文安徽大学商学院安徽合肥230601

惰性与创新一直是一对矛盾体,对于企业协同创新而言,惰性能深刻影响协同创新进程。在文献回顾的基础上,分析了企业间协同创新的惰性因素与原因,认为可以从政府科技政策引导、公共平台建设、高校和科研机构介入、行业协会发挥作用、企业... 详细信息

惰性与创新一直是一对矛盾体,对于企业协同创新而言,惰性能深刻影响协同创新进程。在文献回顾的基础上,分析了企业间协同创新的惰性因素与原因,认为可以从政府科技政策引导、公共平台建设、高校和科研机构介入、行业协会发挥作用、企业创新文化建设和吸收能力培养等方面来克服其惰性。

关键词：协同创新创新惰性创新文化