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Scavenging and release of REE and hFSE by Na-metasomatism in magmatic-hydrothermal systems

Fundamental Research 2024年第2期4卷 315-323页

作者： Wu-Bin Yang he-Cai Niu Ning-bo Li Pete hollings Shannon Zurevinski Roger h.Mitchell Key Laboratory of Mineralogy and Metallogeny/Guangdong Provincial Key Laboratory of Mineral Physics and Materials Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Center for Excellence in Deep Earth Science Guangzhou 510640China Department of Geology Lakehead UniversityThunder BayON P7B 5E1Canada

Exploitable or potentially exploitable deposits of critical metals,such as rare-earth(REE)and high-field-strength elements(hFSE),are commonly associated with alkaline or peralkaline igneous ***,the origin,transport and concentration of these metals in peralkaline systems remains poorly *** study presents the results of a mineralogical and geochemical investigation of the Na-metasomatism of alkali amphiboles and clinopyroxenes from a barren peralkaline granite pluton in NE China,to assess the remobilization and redistribution of REE and hFSE during magmatic-hydrothermal *** amphiboles and aegirine-augites from the peralkaline granites show evolutionary trends from sodic-calcic to sodic compositions,with increasing REE and hFSE concentrations as a function of increasing Na-index[Na^(#),defined as molar Na/(Na+Ca)ratios].the Na-amphiboles(i.e.,arfvedsonite)and aegirine-augites can be subsequently altered,or breakdown,to form hydrothermal aegirine during late-or post-magmatic *** compositions analyzed by insitu LA-ICPMS show that the primary aegirine-augites have high and variable REE(2194-3627 ppm)and hFSE(4194-16,862 ppm)contents,suggesting that these critical metals can be scavenged by alkali amphiboles and *** to the primary aegirine-augites,the presentative early replacement aegirine(Aeg-I,Na^(#)=0.91-0.94)has notably lower REE(1484-1972)and hFSE(4351-5621)*** contrast,the late hydrothermal aegirine(Aeg-II,Na^(#)=0.92-0.96)has significantly lower REE(317-456 ppm)and hFSE(6.44-72.2 ppm)*** that the increasing Na^(#)from aegirine-augites to hydrothermal aegirines likely resulted from Na-metasomatism,a scavenging-release model can explain the remobilization of REE and hFSE in peralkaline granitic *** scavenging and release of REE and hFSE by Na-metasomatism provides key insights into the genesis of globally significant REE and hFSE *** high Na-index of th

关键词： Critical metals Alkali amphiboles Na-metasomatism REE and hFSE Na-index(Na^(#))

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Exploration of cardiac rehabilitation nursing for elderly patients with myocardial infarction based on individualized cardiac rehabilitation

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World journal of Clinical Cases 2024年第2期12卷 256-266页

作者： hua-Ning Liu bo Gao Department of Geriatrics General Hospital of the YangTze River ShippingWuhan Brain HospitalWuhan 430015Hubei ProvinceChina Department of Cardiology Suizhou Central HospitalAffiliated Hospital of Hubei University of MedicineSuizhou 441300Hubei ProvinceChina

BACKGROUND Myocardial infarction is a high-risk condition prevalent among the elderly population,often leading to adverse clinical manifestations such as reduced cardiopulmonary function,anxiety,and depression ***,cardiac rehabilitation holds immense importance in mitigating these *** To evaluate the effect of individualized cardiac rehabilitation on blood pressure variability(BPV)and baroreflex sensitivity(BRS)in elderly patients with myocardial *** A cohort of 74 elderly patients diagnosed with myocardial infarction and admitted to our hospital between January 2021 and January 2022 were subjected to random ***,all patients were divided into two groups,namely the research group(n=37)and the control group(n=37),utilizing the number table *** control group received conventional drug treatment and nursing guidance intervention,while the study group underwent individualized cardiac rehabilitation in addition to the interventions received by the control *** patients were continuously intervened for 12 wk,and the BPV of these two groups in the 1st wk(T0),the 4th wk(T1)and the 12th wk(T2)were compared,BRS,changes in cardiopulmonary function measures,and adverse cardiovascular *** Of 24 h diastolic BPV,24 h systolic BPV,carbon dioxide ventilation equivalent slope of the research group were lower than those of the control group at T1 and T2,BRS,peak heart rate and systolic blood pressure product,1 min heart rate recovery were higher than those of the control group,and the incidence of adverse events in the research group was lower than that of the control group,the difference was statistically significant(Pthis study,we found that after individualized cardiac rehabilitation in elderly patients with myocardial infarction,BPV and BRS can be effectively improved,cardiac function is significantly enhanced,and a better prognosis is obtained.

关键词： Individualized cardiac rehabilitation Myocardial infarction Variability in blood pressure Baroreflex sensitivity

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A Dietary Supplement Jinghuosu Ameliorates Reproductive Damage Induced by Tripterygium Glycosides

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Chinese journal of Integrative Medicine 2024年第4期30卷 330-338页

作者： MA Jing SUN bo TE Li-ger hUANG Xin ZUO Xin hAN Xiao-ke WANG Shu-song hebei Key Laboratory of Reproductive Medicine Hebei Institute of Reproductive HealthHebei Reproductive Health HospitalShijiazhuang(050071)China Graduate School of hebei Medical University Shijiazhuang(050017)China School of Chemistry and Materials Science Hebei Normal UniversityShijiazhuang(050024)China Xingtai Infertility Specialist hospital XingtaiHebei Province(054000)China

Objective To determine the possible protective effects of Jinghuosu,a dietary supplement(DS),on tripterygium glycosides(TG)-induced reproductive system injury in rats and its underlying *** A reproductive damage model was established in rats by feeding of ***-eight male Sprague Dawley rats were randomly divided into 4 groups using a random number table(n=7 in each):control(C)group,model(M)group,DS group and L-carnitine(LC)*** in M,DS and LC groups received 40 mg/kg TGs *** from the 5th week,after administration of TGs for 4 h every day,rats in DS and LC groups were administered with 2.7 g/kg DS and 0.21 g/kg LC,respectively,for protective treatment over the next 4 *** in Group C continued to receive the control ***-eosin staining was used for histopathological analysis of rat testicular ***-linked immunosorbent assay was performed to measure alkaline phosphatase(ALP),lactate dehydrogenase,alcohol dehydrogenase,total antioxidant capacity(T-AOC),superoxide dismutase,glutathione peroxidase(GSh-Px),and malondialdehyde(MDA)*** assay was used to determine the serum testosterone *** real-time PCR and Western blotting were conducted to analyze the expression of genes and proteins related to the testosterone synthesis pathway and the nuclear factor erythroid 2-related factor 2/heme oxygenase 1 antioxidant *** Oral administration of TGs induced significant increases in the testicular levels of zinc transporter 1 and MDA(Pthe other hand,sperm concentration,sperm motility,and serum testosterone,serum zinc,testicular zinc,Zrt-,Irt-like protein 1,ALP,luteinizing hormone(Lh)receptor,steroidogenic acute regulatory protein,Cytochrome P450 family 11 subfamily A member 1,3β-hydroxysteroid dehydrogenase 1 T-AOC,GSh-Px,nuclear factor erythroid 2-related factor 2,heme oxygenase-1 and NAD(P)h:quinone oxidoreductase 1 levels decreased following TG

关键词： dietary supplement Jinghuosu tripterygium glycosides reproductive damage infertility

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本振调制型高重复频率远距离脉冲激光相干测距

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中国激光 2024年第6期51卷 206-219页

作者：吴姿妍眭晓林刘波赵晓龙梅博张奕康李丰君中国电子科技集团公司第十一研究所固体激光技术重点实验室北京100015

为了解决静态目标高重复频率远距离激光相干测距过程中出现的多盲距点和距离模糊问题,对激光测距发射波形、本振波形以及解算方法进行研究。对发射波形和本振波形进行不同斜率的线性调制,将最远可测目标信息调制到本振光端,探测器对回... 详细信息

为了解决静态目标高重复频率远距离激光相干测距过程中出现的多盲距点和距离模糊问题,对激光测距发射波形、本振波形以及解算方法进行研究。对发射波形和本振波形进行不同斜率的线性调制,将最远可测目标信息调制到本振光端,探测器对回波相干信号进行探测,采集卡进行数据采集。采用高精度的脉冲压缩数据处理方法得到匹配滤波结果,并进行距离解算分析。仿真和实验结果表明,该测距方案可以有效解决因高重复频率产生的距离模糊问题,同时避免因脉冲发射时刻光泄漏带来的多点盲距问题。在64μs重复周期、2μs脉宽发射信号和512μs重复周期连续调频本振光条件下,实现模拟29.0525 km目标(延时光纤58.105 km)的探测。该方案可满足高重复频率远距离脉冲激光相干测距无模糊、无间断的测量要求。

关键词：遥感高重复频率本振调制距离模糊盲距

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Novel ternary metals-based telluride electrocatalyst with synergistic effects of high valence non-3d metal and oxophilic Te for ph-universal hydrogen evolution reaction

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journal of Energy Chemistry 2023年第5期80卷 736-743,I0015页

作者： Seunghwan jo Wenxiang Liu Yanan Yue Ki hoon Shin Keon Beom Lee hyeonggeun Choi bo hou Jung Inn Sohn Division of Physics and Semiconductor Science Dongguk UniversitySeoul 04620Republic of Korea School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072HubeiChina School of Physics and Astronomy Cardiff UniversityCardiff CF243AAWalesUK

Electrocatalyst designs based on oxophilic foreign atoms are considered a promising approach for developing efficient ph-universal hydrogen evolution reaction(hER)electrocatalysts by overcoming the sluggish alkaline hER ***,we design ternary transition metals-based nickel telluride(Mo WNi Te)catalysts consisting of high valence non-3d Mo and W metals and oxophilic Te as a first demonstration of non-precious heterogeneous electrocatalysts following the bifunctional *** Mo WNi Te showed excellent hER catalytic performance with overpotentials of 72,125,and 182 mV to reach the current densities of 10,100,and 1000 mA cm^(-2),respectively,and the corresponding Tafel slope of 47,52,and 58 mV dec-1in alkaline media,which is much superior to commercial Pt/***,the hER performance of Mo WNi Te is well maintained up to 3000 h at the current density of 100 mA cm^(-2).It is further demonstrated that the Mo WNi Te exhibits remarkable hER activities with an overpotential of 45 mV(31 mV)and Tafel slope of 60 mV dec-1(34 mV dec-1)at 10 mA cm^(-2)in neutral(acid)*** superior hER performance of Mo WNi Te is attributed to the electronic structure modulation,inducing highly active low valence states by the incorporation of high valence non-3d transition *** is also attributed to the oxophilic effect of Te,accelerating water dissociation kinetics through a bifunctional catalytic mechanism in alkaline *** functional theory calculations further reveal that such synergistic effects lead to reduced free energy for an efficient water dissociation process,resulting in remarkable hER catalytic performances within universal ph environments.

关键词： Telluride catalyst Oxophilic effect high valence non-3d metal Bifunctional mechanism ph-universal hydrogen evolution reaction

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hafnium carbide structural foams synthesized from polymer precursors

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中国有色金属学会会刊：英文版 2006年第A2期16卷 85-88页

作者： FAN hai-bo YANG hong N. K. RAVALA h. C. WIKLE III R. h. ZEE B. A. ChIN 275 Wilmore Labs Auburn University Auburn AL 36849-5341 USA

hafnium carbide (hfC) was applied in space and aerospace due to its ultra high melting temperature, high specific strength and moderate oxidation resistance. A novel synthesizing method was used to produce low density and high strength hfC structural foams through the thermolysis and pyrolysis of hf containing polymer precursors (mixing of hafnium trifluoroacetylacetonate and epoxy) under vacuum atmosphere. the X-ray diffraction analysis shows that the produced foam is primarily composed of hfC containing 9%-10% hfO2. Several polymer powder compaction methods were used to improve the mechanical properties of hfC foam. Compression strengths of 200 MPa are achieved for hfC foams with density of 1.9 g/cm3 (total porosity about 85%). the proposed methodology of synthesizing hfC foam has the advantages of simple, inexpensive and less production time than alternate methods.

关键词：聚合物前提碳化铪结构性泡沫保护性涂层合成力学性质超高温

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Influence of Microstructures on Polarization Resistance and hydrogen-Induced Cracking of a Micro-Alloyed Steel Submitted to Different Cooling Rates

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journal of Iron and Steel Research International 2011年第S1期18卷 168-172页

作者： González M R Martins de Araújo D S Goldenstein h Alonso-Falleiros N Departamento de Engenharia Metalúrgica e de Materiais EscolaPolitécnicaUniversidade de Sao Paulo-SP-Brasil

the effect of different microstructures on the polarization resistance (Rp) and the hydrogen-induced cracking (hIC) of a micro-alloyed steel austenitized and submitted to different cooling rates was *** 19.1 x 6 x 2 mm,containing the whole thickness of the plate were extracted from a 20 mm plate and heat treated on a quenching dilatometer,were submitted to Rp and hIC corrosion *** Rp and hIC tests followed as close as possible ASTM G59 and NACE standard TM0284-2003,in this case,modified only with regard to the size of the *** samples transformed from austenite by a slow cooling (cooling rate of 0.5℃.s-1) showed higher susceptibility to hydrogen-induced cracking,with large cracks in the middle of the sample propagating along segregation bands,corresponding to the centerline of the plate *** cooling rates of 10℃.s-1,only small cracks were found in the matrix and micro cracks nucleated at non-metallic *** higher cooling rates (40℃.s-1) very few small cracks were detected,linked to non-metallic *** result suggests that structures formed by polygonal structures and segregation bands (were eutectoid microconstituents predominate) have higher susceptibility to *** predominantly formed by acicular ferrite make it difficult to propagate the cracks among non-oriented and interlaced acicular ferrite *** segregation bands containing eutectoid products also help inhibit cracking and crack propagation;segregation bands can function as pipelines for hydrogen diffusion and offer a path of stress concentration for the propagation of cracks,frequently associated to non-metallic *** resistance essays performed on the steel in theas received condition,prior to any heat treatment,showed larger differences between the regions of the plate,with a considerably lower Rp in the *** austenitization heat treatments followed by cooling rates of 0.5 e 10℃.s-1 made more uniform the

关键词： hydrogen induced cracking polarization resistance micro-alloyed steel control cooling

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DiI标记的大鼠骨髓间充质干细胞与乳鼠心肌细胞在聚己内酯薄膜上接触共培养制作心肌补片的实验研究

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中华心血管病杂志 2024年第5期52卷 525-531页

作者：张子畅穆军升周帆伯平尤斌首都医科大学宣武医院心脏外科北京100053 首都医科大学附属北京安贞医院心脏外科、北京市心肺血管疾病研究所北京100029 解放军总医院第三医学中心超声科北京100039

目的探讨在聚己内酯薄膜上将DiI标记的骨髓间充质干细胞(BMSCs)与乳鼠心肌细胞接触共培养制作心肌补片的可能机制。方法选取5~6周龄SD大鼠2只,分离培养获得SD大鼠BMSCs,流式细胞术鉴定表面抗原。选取乳鼠15只,分离培养获得乳鼠心肌细胞... 详细信息

目的探讨在聚己内酯薄膜上将DiI标记的骨髓间充质干细胞(BMSCs)与乳鼠心肌细胞接触共培养制作心肌补片的可能机制。方法选取5~6周龄SD大鼠2只,分离培养获得SD大鼠BMSCs,流式细胞术鉴定表面抗原。选取乳鼠15只,分离培养获得乳鼠心肌细胞。BMSCs培养至3代,使用DiI染料标记BMSCs。在聚己内酯薄膜上将DiI标记的BMSCs与心肌细胞接触共培养并设为实验组,对照组中将心肌细胞替换为等量未标记的BMSCs。共培养后24 h在荧光显微镜下观察细胞生长情况,并用扫描电镜观察共培养情况。共培养后7 d对细胞进行免疫荧光染色检测心肌标志物表达,在荧光显微镜下观察聚己内酯薄膜上BMSCs表达心肌标志物的情况。共培养的第1、7天使用流式细胞术分析BMSCs的干细胞分化率。使用钙黄绿素单独对心肌细胞染色,再在聚己内酯薄膜上将其与DiI标记的BMSCs接触共培养,观察细胞间染料转移,并对细胞进行免疫荧光染色,检测缝隙连接蛋白43的表达,观察缝隙连接与接触共培养之间的关系。结果流式细胞术鉴定示BMSCs表面CD90、CD44h强阳性,CD11b/c、CD45阴性。共培养后24 h,荧光显微镜下观察到细胞依附于聚己内酯薄膜上,DiI标记的BMSCs发红光,未标记的心肌细胞不发光;扫描电镜下观察到聚己内酯薄膜上细胞数量多,细胞状态正常。共培养第7天,部分DiI标记的BMSCs表达心肌肌钙蛋白T、α-心肌肌动蛋白。流式细胞术分析示第7天实验组的干细胞分化率高于对照组[(20.12±0.15)%比(3.49±0.20)%,P<0.05]。共培养后第2天,缝隙连接蛋白43免疫荧光染色结果示部分BMSCs可见明显绿色点状荧光;共培养后第3天,染料转移试验示部分BMSCs发出明显绿色荧光。结论DiI标记的BMSCs与心肌细胞在聚己内酯薄膜上接触共培养可以制作心肌补片,并且接触共培养促进分化形成心肌补片的机制可能与缝隙连接以及缝隙连接介导的细胞间信号通路有关。

关键词：干细胞心肌补片接触共培养 DiI标记缝隙连接

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额尔齐斯河中的高体雅罗鱼胚胎和仔鱼发育观察

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湿地科学 2024年第1期22卷 16-24页

作者：韩豪祥金洪宇廉杰马波中国水产科学研究院黑龙江水产研究所黑龙江哈尔滨150070 上海海洋大学上海201306

为了了解高体雅罗鱼(Leuciscus idus)胚胎发育的规律,以额尔齐斯河中的野生高体雅罗鱼为亲本,通过人工授精获得受精卵,对其胚胎发育的时序和各个时期的特征进行了观察、详细描述、记录和分析。研究结果表明,在水温为(13.34±0.14)℃条件... 详细信息

为了了解高体雅罗鱼(Leuciscus idus)胚胎发育的规律,以额尔齐斯河中的野生高体雅罗鱼为亲本,通过人工授精获得受精卵,对其胚胎发育的时序和各个时期的特征进行了观察、详细描述、记录和分析。研究结果表明,在水温为(13.34±0.14)℃条件下,高体雅罗鱼的胚胎历经234 h 20 min出膜,共需积温3 136.36℃·h;高体雅罗鱼的胚胎发育过程经历了受精卵期、卵裂期、囊胚期、原肠胚期、神经胚期、器官形成期和孵化期共7个时期(进一步细分为26个时期);其中,孵化期所需要的积温最多,其次为器官形成期,囊胚期、卵裂期、神经胚期、原肠期、受精卵期所需要的积温依次减少;历经96 h,出膜仔鱼的眼、消化道、鳃盖等器官完全形成,已经可以开口摄食,但是,此时为内源性和外源性营养混合吸收的方式,直到第5天,卵黄囊被吸收完毕,仔鱼的营养吸收方式完全转变为外源性营养吸收方式。在早期的生长和发育过程中,高体雅罗鱼的仔鱼能够通过食物来源的快速转变、器官的快速发育等一系列生理变化,增强自身对环境的适应能力,提高自身的成活率。因此,深入研究高体雅罗鱼早期发育时期的生物学特性,对于提高其苗种成活率和未来进一步开展该物种的人工繁育工作具有重要意义。

关键词：高体雅罗鱼人工繁殖胚胎仔鱼发育额尔齐斯河

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西北内陆区降水稳定同位素时空分布特征及其水汽来源

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环境科学 2024年第4期45卷 2080-2095页

作者：张炎炎辛存林郭小燕张博陈宁史延飞西北师范大学地理与环境科学学院兰州730070 中国科学院西北生态环境资源研究院兰州730000

综合分析西北内陆区97个研究站点的降水稳定同位素数据,并结合相关气象资料,揭示了西北内陆区降水稳定同位素δ^(18)O、δD和d-excess时空分布特征,明确了海拔、经纬度、温度和降雨量对降水δ^(18)O的影响;利用水汽通量和hYSPLIT模型追... 详细信息

综合分析西北内陆区97个研究站点的降水稳定同位素数据,并结合相关气象资料,揭示了西北内陆区降水稳定同位素δ^(18)O、δD和d-excess时空分布特征,明确了海拔、经纬度、温度和降雨量对降水δ^(18)O的影响;利用水汽通量和hYSPLIT模型追踪了大气降水的水汽来源.同时,根据关键自然地理要素的空间差异将西北内陆区划分为4个子区域,对上述内容分区域进行系统分析和对比.结果表明:(1)西北内陆区降水δ^(18)O和δD的变化范围分别为-21.20‰~1.70‰和-144.20‰~5.21‰,d-excess波动范围为-20.37‰~46.48‰,δ^(18)O、δD和d-excess均存在显著的空间变化和季节变化特征,河西内陆区和塔里木地区δ^(18)O和δD值相对偏正,柴达木-青海湖区和准噶尔-吐哈地区δ^(18)O和δD偏负.(2)西北内陆区大气降水线方程的斜率和截距均小于中国和全球大气降水线,4个子区域亦低于全球水线,其中塔里木地区斜率最低.(3)西北内陆区海拔效应为-0.04‰·(100 m)^(-1),其中河西内陆区和塔里木地区呈显著负相关;降水δ^(18)O与经度呈显著正相关,而与纬度呈不显著负相关.(4)西北内陆区普遍存在显著的温度效应,呈西北高东南低的空间特征;受气温和地形影响,降雨量效应较微弱.(5)西北内陆区水汽来源全年主要为西风水汽输送,冬季受到极地气团影响,夏季受季风水汽的入侵,部分区域会出现极端降水事件;过量氘夏季贫化、冬季富集,与相对湿度呈正相关,表明西北内陆区降水还受局地水汽再循环影响.

关键词：西北内陆区大气降水稳定同位素水汽来源过量氘

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