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Crystalline and amorphous metal sulfide composite electrode materials with long cycle life:Preparation and performance of hybrid capacitors
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作者 DING Ning WANG Siyu +4 位作者 YU Shihua XU Pengcheng HAN Dandan SHI Dexin ZHANG Chao 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1784-1794,共11页
Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realiz... Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realized the defect regulation of crystal NiCo_(2)S_(4) in the core.Taking advantage of the flexible protection of an amor-phous shell and the high capacity of a conductive core with defects,the v-NCS@MS electrode exhibited high specif-ic capacity(1034 mAh·g^(-1) at 1 A·g^(-1))and outstanding rate capability.Moreover,a hybrid supercapacitor was assembled with v-NCS@MS as cathode and activated carbon(AC)as anode,which can achieve remarkably high specific energy of 111 Wh·kg^(-1) at a specific power of 219 W·kg^(-1) and outstanding capacity retention of 80.5%after 15000 cycling at different current densities. 展开更多
关键词 crystalline@amorphous heterostructure NiCo2s4@Mos2 hybrid supercapacitor defect design long cycle life
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Representation of an Integer by a Quadratic Form through the Cornacchia Algorithm
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作者 Moumouni Djassibo Woba 《Applied Mathematics》 2024年第9期614-629,共16页
Cornachia’s algorithm can be adapted to the case of the equation x2+dy2=nand even to the case of ax2+bxy+cy2=n. For the sake of completeness, we have given modalities without proofs (the proof in the case of the equa... Cornachia’s algorithm can be adapted to the case of the equation x2+dy2=nand even to the case of ax2+bxy+cy2=n. For the sake of completeness, we have given modalities without proofs (the proof in the case of the equation x2+y2=n). Starting from a quadratic form with two variables f(x,y)=ax2+bxy+cy2and n an integer. We have shown that a primitive positive solution (u,v)of the equation f(x,y)=nis admissible if it is obtained in the following way: we take α modulo n such that f(α,1)≡0modn, u is the first of the remainders of Euclid’s algorithm associated with n and α that is less than 4cn/| D |) (possibly α itself) and the equation f(x,y)=n. has an integer solution u in y. At the end of our work, it also appears that the Cornacchia algorithm is good for the form n=ax2+bxy+cy2if all the primitive positive integer solutions of the equation f(x,y)=nare admissible, i.e. computable by the algorithmic process. 展开更多
关键词 Quadratic form Cornacchia Algorithm Associated Polynomials Euclid’s Algorithm Prime Number
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Life′s Simple 7干预减轻Her⁃2阳性乳腺癌患者化疗相关心血管系统损害的研究 被引量:2
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作者 吴军 崔伟燕 +2 位作者 李平 张青凤 欧月珍 《实用医学杂志》 CAS 北大核心 2023年第13期1647-1651,1656,共6页
目的探讨Life′s Simple 7(LS7)干预减轻Her⁃2阳性乳腺癌患者根治术后化疗相关心血管系统损害的作用。方法将120例Her⁃2阳性并接受标准化乳腺癌化疗的患者随机等量分为对照组及LS7组,对照组为标准化疗方案,LS7组为对照组基础上给予LS7干... 目的探讨Life′s Simple 7(LS7)干预减轻Her⁃2阳性乳腺癌患者根治术后化疗相关心血管系统损害的作用。方法将120例Her⁃2阳性并接受标准化乳腺癌化疗的患者随机等量分为对照组及LS7组,对照组为标准化疗方案,LS7组为对照组基础上给予LS7干预12个月,后续通过比较两组治疗前后心血管系统损伤程度、焦虑、抑郁及生活质量等指标评价其对心血管系统损害的改善作用。结果相较于对照组,LS7组LS7总评分及7项心血管健康指标均优于对照组(P<0.05),LS7组LVEF较高(P<0.05)、NT⁃proBNP较低(P<0.05),焦虑和抑郁评分较低(P<0.05)、生活质量评分较高(P<0.05)。结论LS7干预可显著减轻Her⁃2阳性乳腺癌化疗相关心血管系统损害并改善乳腺癌患者的心理状况和生活质量,值得在临床推广。 展开更多
关键词 lifes simple 7 乳腺癌 心血管健康 心理状况 生活质量
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基于断裂力学的腐蚀钢丝疲劳S-N曲线研究 被引量:1
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作者 叶华文 叶杨帆 +2 位作者 邓雪峰 杨军川 徐勋 《铁道科学与工程学报》 EI CAS CSCD 北大核心 2024年第5期1990-2000,共11页
高强冷拔钢丝因其优异的力学性能被广泛应用于缆索承重结构,服役过程中钢丝腐蚀与断裂威胁着结构安全。钢丝腐蚀后表面的蚀坑因应力集中效应易产生疲劳裂纹,因此腐蚀钢丝剩余疲劳寿命主要取决于裂纹的扩展阶段,且裂纹扩展受到腐蚀程度(... 高强冷拔钢丝因其优异的力学性能被广泛应用于缆索承重结构,服役过程中钢丝腐蚀与断裂威胁着结构安全。钢丝腐蚀后表面的蚀坑因应力集中效应易产生疲劳裂纹,因此腐蚀钢丝剩余疲劳寿命主要取决于裂纹的扩展阶段,且裂纹扩展受到腐蚀程度(初始损伤)的显著影响。精确表征腐蚀程度并准确评估服役期钢丝腐蚀后的剩余寿命,仍是亟待解决的维修难题。首先采用蚀坑最大深度表征钢丝腐蚀程度,以应力强度因子幅作为裂纹扩展驱动力指标,基于断裂力学的Paris公式建立受拉钢丝裂纹扩展理论模型,进而推导腐蚀钢丝的疲劳S-N曲线。大量既有的腐蚀钢丝疲劳试验结果与理论预测值的比较验证了所提理论模型及疲劳S-N曲线的合理性和有效性。含多个蚀坑的钢丝裂纹扩展有限元模拟表明,等效单裂纹适用于多腐蚀坑钢丝疲劳寿命的简化分析。参数分析表明,蚀坑深度和腐蚀环境是腐蚀钢丝疲劳强度的关键影响因素,而应力比和疲劳加载频率影响较小,所提出的S-N曲线在钢丝常规服役条件下适用于评估其剩余寿命,可得到合理的预测结果。基于断裂力学所提的理论方法和疲劳S-N曲线可为腐蚀钢丝的疲劳强度和寿命评估提供参考。 展开更多
关键词 冷拔钢丝 腐蚀 剩余寿命 s-N曲线 蚀坑深度
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Characteristics of life-form and growth-form of plant species in an alpine ecosystem of North-West Himalaya 被引量:4
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作者 R. K. Vashistha Neelam Rawat +3 位作者 A. K. Chaturvedi B. P. Nautiyal P. Prasad M. C. Nautiyal 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第4期501-506,共6页
The present study was conducted in the alpine pastures of Tungnath (30° 14' N and 79° 13' E) to observe life-form and growth-form patterns of alpine plant species under grazed and ungrazed conditions and... The present study was conducted in the alpine pastures of Tungnath (30° 14' N and 79° 13' E) to observe life-form and growth-form patterns of alpine plant species under grazed and ungrazed conditions and to work out the plant life form spectrum. Species were categorized as plant habit, height and length of growth-cycle and life-form classes according to Raunkiaer's system. The results show that in total of 68 species at grazed site, hemicryptophytes (He) accounted for 50.00% species, followed by cryptophytes (26.47%), chamaephytes (16.18%), phanemphytes (4.41%) and therophytes (2.94%). At the ungrazed site in 65 plant species, hemicryptophytes (He) accounted fo'r 49.23% species, cryptophytes (26.15%), chamaephytes (15.38%), phanerophytes (6.15%) and ther6phytes (3.08 % species). In general, hemicrptophyte are dominant^in both sites i.e. graged and ungrazed. Growth form categories were classified as forbs, shrubs, grasses and sedges'and undershrubs, according to plant habit and height. On the basis of length of the growth cycle, species were categorized as plant species of short growth cycle, intermediate growth cycle and long growth cycle. The short forbs of plant habit and height, had the highest emergence, and grasses and sedges had the lowest emergence in representative species. Percentage of species with long growth cycle was highest in both sites. 展开更多
关键词 ALPINE biological spectrum growth form HIMALAYA life
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Ecological biomass allocation strategies in plant species with different life forms in a cold desert, China 被引量:5
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作者 FAN Lianlian DING Junxiang +1 位作者 MA Xuexi LI Yaoming 《Journal of Arid Land》 SCIE CSCD 2019年第5期729-739,共11页
Biomass allocation patterns among plant species are related to their adaptive ecological strategies. Ephemeral, ephemeroid and annual plant life forms represent three typical growth strategies of plants that grow in a... Biomass allocation patterns among plant species are related to their adaptive ecological strategies. Ephemeral, ephemeroid and annual plant life forms represent three typical growth strategies of plants that grow in autumn and early spring in the cold deserts of China. These plants play an important role in reducing wind velocity in the desert areas. However, despite numerous studies, the strategies of biomass allocation among plant species with these three life forms remain contentious. In this study, we conducted a preliminary quadrat study during 2014–2016 in the southern part of the Gurbantunggut Desert, China, to investigate the allocation patterns of above-ground biomass(AGB) and below-ground biomass(BGB) at the individual level in 17 ephemeral, 3 ephemeroid and 4 annual plant species. Since ephemeral plants can germinate in autumn, we also compared biomass allocation patterns between plants that germinated in autumn 2015 and spring 2016 for 4 common ephemeral species. The healthy mature individual plants of each species were sampled and the AGB, BGB, total biomass(TB), leaf mass ratio(LMR) and root/shoot ratio(R/S) were calculated for 201 sample quadrats in the study area. We also studied the relationships between AGB and BGB of plants with the three different life forms(ephemeral, ephemeroid and annual). The mean AGB values of ephemeral, ephemeroid and annual plants were 0.806, 3.759 and 1.546 g/plant, respectively, and the mean BGB values were 0.106, 4.996 and 0.166 g/plant, respectively. The mean R/S value was significantly higher in ephemeroid plants(1.675) than in ephemeral(0.154) and annual(0.147) plants. The mean LMR was the highest in annual plants, followed by ephemeroid plants and ephemeral plants, reflecting the fact that annual plants allocate more biomass to leaves, associated with their longer life span. Biomass of ephemeral plants that germinated in autumn was significantly higher than those of corresponding plants that germinated in spring in terms of AGB, BGB and TB. However, the R/S value was similar in plants that germinated in autumn and spring. The slope of regression relationship between AGB and BGB differed significantly among the three plant life forms. These results support different biomass allocation hypotheses. Specifically, at the individual level, the AGB and BGB partitioning supports the allometric hypothesis for ephemeroid and annual plants and the isometric hypothesis for ephemeral plants. 展开更多
关键词 above-ground BIOMAss BELOW-GROUND BIOMAss plant life forms HERBACEOUs species ALLOMETRIC HYPOTHEsIs IsOMETRIC HYPOTHEsIs Gurbantunggut Desert
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Variations of plant life form diversity along the Northeast China Transect and its direct gradient analysis 被引量:2
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作者 WANGRen-zhong GAOQiong2 TANGHai-ping: 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第4期547-551,共5页
Plant life form diversity and its direct gradient analysis on a larger scale climate change gradient were tested, based on the data from Northeast China Transect platform. The results showed that the species numbers, ... Plant life form diversity and its direct gradient analysis on a larger scale climate change gradient were tested, based on the data from Northeast China Transect platform. The results showed that the species numbers, life form richness and life form diversity were relative higher at the eastern forests and the ecotone between typical vegetation, while those on the meadow grasslands and typical steppes were lower. Although plant life forms can reflect the climate variations, life form diversity is not consistent with the major global gradient along the NECT. 展开更多
关键词 northeast China transect plant life form diversity ECOTONE gradient analysis
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Antioxidant systems of aquatic macrophytes in three life forms:a case study in Lake Erhai,China 被引量:1
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作者 YUAN Changbo ZHU Tianshun +3 位作者 CAO Te XI Yilong ZHANG Xiaolin NI Leyi 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第2期665-674,共10页
Antioxidant systems are vital in life activities of macrophytes. Species with diff erent life forms need to cope with distinct environments by modifying physiological characters, especially antioxidant systems. In ord... Antioxidant systems are vital in life activities of macrophytes. Species with diff erent life forms need to cope with distinct environments by modifying physiological characters, especially antioxidant systems. In order to find diff erences among life forms and consequence of lake eutrophication, we studied three antioxidant enzymes activity (superoxide dismutase (SOD), ascorbate oxidase (APX) and catalase (CAT)) and total soluble phenolics (TP) content in leaves of 26 macrophyte species in September 2013 in Lake Erhai, China. We found that antioxidation varied accordingly with life forms. The activities of SOD and APX in emergent macrophytes (EM) and floating-leaved macrophytes (FM) were much lower than those of submerged macrophytes (SM). On the contrary, TP content was much higher in EM and FM species. There was a negative correlation between TP and antioxidant enzyme activities (CAT and APX). The results suggested that EM and FM species rely on phenolics might to adapt to adverse environments (higher herbivores predation pressure and UV radiation intensity), while SM species more rely on antioxidant enzymes possibly due to lower demand for antioxidation and/or lack of light and inorganic C availability for phenolics synthesis. We also found FM species represent highest fitness in term of antioxidant system, which would lead to overgrowth of FM species and littoral zone bogginess during lake eutrophication. Finally, it is necessary to carry out the verification experiment under the control condition in the later stage, especially for the dominant ones in eutrophic lakes, to understand the exact adaptive mechanisms of them. 展开更多
关键词 MACROPHYTEs life forms phenolics ANTIOXIDANT ENZYMEs EUTROPHICATION
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Life form and geographical distribution of plants in Posthband region,Khonj,Fars Province,Iran 被引量:2
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作者 Gholamhosein Moradi Mohammad Reza Marvie Mohadjer +2 位作者 Ghavamodin Zahedi Amiri Anoushirvan Shirvany Nosratollah Zargham 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第2期201-206,I0006,共7页
A study was conducted to identify plant species,diversity,life form and relevant species to Mediterranean climate,Irano-Torunian and Sahara-Sindian in Postband region(N 27°58'4"-28°2'16",E 53°17'3... A study was conducted to identify plant species,diversity,life form and relevant species to Mediterranean climate,Irano-Torunian and Sahara-Sindian in Postband region(N 27°58'4"-28°2'16",E 53°17'34"-53°22'30").In total,95 species belonging to 29 families and 69 genera of flora were surveyed and identified from December 2006 to June 2008.Composite and Gramineae were important families in terms of species frequency.According to Raunkiaer's system and using X^2 tests,the life-form spectrum showed that therophytes accounted for 47% of all species,and hemicryptophytes for 31%,phanerophytes for 12%,chamaeophyte for 7%,and cryptophytes for 3%.In geographical distribution,29% species with the most frequency belonged to Irano-Torunian region.Results show that therophytes were more than normal spectrum and phaneropytes were less than normal spectrum,which was in agreement with data obtained in arid climate. 展开更多
关键词 geographical distribution life form Khalije-omani forest FLORA Posthband
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液压成形对液体火箭发动机多层增强S型波纹管结构疲劳寿命的影响
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作者 张涵 张东升 朱卫平 《火箭推进》 CAS 北大核心 2024年第1期113-126,共14页
完善液体火箭发动机燃气摇摆装置中增强S型波纹管组件的疲劳寿命评估方法,提高其疲劳寿命预测精度,是发展可重复使用液体火箭发动机的重要课题之一。针对多层增强S型波纹管,为了计算其液压成形后的实际寿命数据,了解成形工艺对其疲劳寿... 完善液体火箭发动机燃气摇摆装置中增强S型波纹管组件的疲劳寿命评估方法,提高其疲劳寿命预测精度,是发展可重复使用液体火箭发动机的重要课题之一。针对多层增强S型波纹管,为了计算其液压成形后的实际寿命数据,了解成形工艺对其疲劳寿命的影响,提出一种充分考虑成形制备过程对结构不同区域几何构型和材料力学性能造成差异化影响后的波纹管疲劳寿命分析方法。该方法基于成形仿真和材料拉伸试验结果,构建实际波纹管有限元模型并进行三维仿真分析,得到其在高内压和不同摆动工况下结构危险点的循环载荷信息,并根据波纹管结构的低周疲劳失效特点采用子午向应力应变数据,以及经过平均应力应变修正的Manson-Coffin(M-C)公式对波纹管的循环寿命进行估算和对比分析。结果表明:波纹管疲劳寿命薄弱点位置和大小均与循环摆角有关;在预测计算中考虑液压成形作用影响更接近实际场景,所得结构疲劳寿命大小和所在区域均与理论模型值存在差异,在结构设计、优化和健康监测中不应忽视其影响。 展开更多
关键词 重复使用液体火箭发动机 增强s型波纹管 疲劳寿命 液压成形
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Factors influencing quality of life in Chinese patients with dementia: a systematic review
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作者 Jin-Long Ma Bao-Jian Wei Yan-Mei Lang 《Aging Communications》 2023年第2期35-42,共8页
Background:Dementia is a group of nervous system diseases characterized by progressive cognitive decline,leading to a loss of self-care ability and a decline in well-being.This places a significant burden on the globa... Background:Dementia is a group of nervous system diseases characterized by progressive cognitive decline,leading to a loss of self-care ability and a decline in well-being.This places a significant burden on the global healthcare system,with Chinese patients accounting for approximately one-quarter of the world’s dementia cases.Therefore,it is crucial to identify factors that impact the quality of life(QOL)among elderly Chinese individuals with dementia.Method:To achieve this,we conducted a comprehensive search of several databases,including PubMed,Embase,Web of Science,the Cochrane Library,China National Knowledge Infrastructure,Wanfang Data,China VIP Database and China Biomedical Literature Database.We reviewed cross-sectional studies from the inception of these databases until March 27,2022.QOL outcomes were assessed using standardized scales in the studies included in this review.Results:The search yielded a total of 1,235 relevant articles,from which we finally included 21 cross-sectional studies and one longitudinal study after rigorous quality assessment.Among these,10 studies were classified as high quality,while 12 were classified as fair quality.Through our analysis,we identified 28 patient-rated QOL factors and 14 caregiver-rated QOL factors.These factors were categorized into three groups:patient,disease-related and caregiver.Factors commonly found to influence patient-rated QOL included age,education,marital status,depression,self-care ability,dementia severity,cognitive function,behavioral and psychological symptoms of dementia and caregiver burden.Similarly,factors commonly influencing caregiver-rated QOL included economic status,depression,self-care ability,dementia severity,cognitive function,behavioral and psychological symptoms of dementia and caregiving time.Conclusion:This review clarifies the factors that influence the QOL of Chinese individuals with dementia.When implementing interventions,it is crucial to consider the differences between patient-rated QOL and caregiver-proxy-rated QOL,as well as their respective influencing factors. 展开更多
关键词 DEMENTIA Alzheimer’s disease quality of life social support protective factors
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凤太矿集区八卦庙金矿区脉状铅锌矿化的物质来源研究:硫化物原位S-Pb同位素证据
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作者 高炫宇 李宇轩 +2 位作者 梁文静 袁洪林 安芳 《地质科学》 CAS CSCD 北大核心 2024年第5期1438-1452,共15页
秦岭造山带凤太矿集区内发育层状—似层状和脉状两种类型的铅锌矿化,部分脉状铅锌矿化伴生产于金矿床中,其成矿物质来源仍未得到较好的约束。论文以八卦庙金矿区的脉状铅锌矿体为主要研究对象,采用硫化物原位微区S-Pb同位素研究方法,探... 秦岭造山带凤太矿集区内发育层状—似层状和脉状两种类型的铅锌矿化,部分脉状铅锌矿化伴生产于金矿床中,其成矿物质来源仍未得到较好的约束。论文以八卦庙金矿区的脉状铅锌矿体为主要研究对象,采用硫化物原位微区S-Pb同位素研究方法,探讨了脉状铅锌矿化的成矿物质来源。八卦庙金矿区的脉状铅锌矿化主要受NE和NW向断裂或裂隙控制,矿脉宽度通常为2~20 cm。矿石呈团块状或浸染状构造,其中矿石矿物以方铅矿和闪锌矿为主,另有少量黄铜矿和黄铁矿,脉石矿物有石英、白云母、绢云母和少量方解石、白云石等碳酸盐矿物。硫化物原位S-Pb同位素分析结果显示,矿石中闪锌矿的δ^(34)S值相对集中(15.03‰~17.11‰),而黄铜矿(14.76‰~19.91‰)和方铅矿(12.12‰~21.88‰)的δ^(34)S值则变化较大;方铅矿的铅同位素组成非常均一。通过与区内可能物质源区S-Pb同位素对比研究,认为八卦庙金矿区脉状铅锌矿化的成矿物质来自于围岩变质过程中释放的变质流体,并有印支期岩浆热液的贡献,总体具有与金矿化相似的成矿物质来源。金矿化和脉状铅锌矿化在八卦庙矿区共生富集但又独立产出,可能受铅锌和金元素在热液体系中明显不同的地球化学行为所控制。 展开更多
关键词 脉状铅锌矿化 八卦庙金矿 硫化物原位s-Pb同位素 物质来源
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具有稚虫迁徙机制的S型自适应混沌蜉蝣算法
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作者 张恒齐 钱谦 《化工自动化及仪表》 CAS 2024年第2期262-273,共12页
针对蜉蝣优化算法(MA)全局搜索能力较弱,对子代优秀个体有效信息利用不够充分的缺点,以及在计算中后期易陷入局部收敛,进而影响优化效果的问题,提出一种具有稚虫迁徙机制的S型自适应混沌蜉蝣优化算法(S-AMA)。S-AMA算法首先采用Logisti... 针对蜉蝣优化算法(MA)全局搜索能力较弱,对子代优秀个体有效信息利用不够充分的缺点,以及在计算中后期易陷入局部收敛,进而影响优化效果的问题,提出一种具有稚虫迁徙机制的S型自适应混沌蜉蝣优化算法(S-AMA)。S-AMA算法首先采用Logistic混沌映射产生蜉蝣种群,增加算法初期种群的多样性;随后,将蜉蝣生命周期进行数学建模,并引入S型生命系数替换原有的重力惯性系数,动态调整算法探索能力和开发能力间的平衡性;最后,根据蜉蝣在缺氧环境下的种群活动,引入稚虫迁徙机制强化子代优秀个体摆脱局部最优的能力,进而更加充分地搜索最优解附近的区域,以增强算法的收敛精度。实验部分将S-AMA应用于标准函数测试集,并分别进行优化对比实验、Wilcoxon秩和检验。结果表明:与对比算法相比,S-AMA算法具有更好的寻优能力、收敛速度及鲁棒性。 展开更多
关键词 s型自适应混沌蜉蝣优化算法(s-AMA) 稚虫迁徙机制 混沌映射 s型生命系数 莱维飞行
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内蒙古根河三道桥铅锌银矿床C-H-O-S同位素和U-Pb定年研究及其意义
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作者 关强兵 刘俊辰 +5 位作者 王义天 胡乔青 何猛 段志辉 党顺安 史新 《矿产勘查》 2024年第4期526-539,共14页
内蒙古根河三道桥大型铅锌银矿床位于大兴安岭得尔布干成矿带中北段,矿体主要呈脉状赋存于火山岩地层中。氢氧同位素研究表明,成矿期石英和绢云母的δD值变化范围为-149.1‰~-156.7‰,δ^(18)OH_(2)O值变化范围为-13.6‰~3.4‰;成矿后... 内蒙古根河三道桥大型铅锌银矿床位于大兴安岭得尔布干成矿带中北段,矿体主要呈脉状赋存于火山岩地层中。氢氧同位素研究表明,成矿期石英和绢云母的δD值变化范围为-149.1‰~-156.7‰,δ^(18)OH_(2)O值变化范围为-13.6‰~3.4‰;成矿后期石英δD值变化范围为-131.9‰~-147.7‰,δ^(18)OH_(2)O值变化范围为-16.5‰~-18.2‰。碳同位素分析结果表明,与矿化有关的方解石δ^(13)C值变化范围为-1.8‰~-3.1‰,δ^(18)O值变化范围为5.3‰~8.6‰。原位S同位素分析结果表明,硫化物的δ^(34)S值变化范围为2.3‰~5.6‰,与其西南侧下护林矽卡岩型铅锌银矿床中的硫化物的δ^(34)S值(1.2‰~5.9‰)基本一致。上述同位素组成特征指示成矿物质主要来源于岩浆热液,在上升到地壳浅部时有一定量的大气降水混入。锆石U-Pb年代学研究表明,矿化的闪长玢岩脉年龄为(136.0±0.7)Ma(MSWD=0.44);未矿化、穿切硫化物微细脉的闪长玢岩脉的锆石U-Pb年龄为(120.8±0.6)Ma(MSWD=0.49)。结合前人相关研究进展,认为三道桥铅锌银矿床形成于136.0~120.8 Ma期间(早白垩世),为伸展构造背景下与浅成侵入岩有关的中温热液型铅锌银矿床。 展开更多
关键词 C-H-O-s同位素 锆石U-Pb定年 成矿物质来源 三道桥铅锌银矿床 内蒙古
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Host plant traits play a crucial role in shaping the composition of epiphytic microbiota in the arid desert,Northwest China
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作者 ZHANG Jun ZHANG Yuanming ZHANG Qi 《Journal of Arid Land》 SCIE CSCD 2024年第5期699-724,共26页
Phyllosphere microorganisms are a crucial component of environmental microorganisms,highly influenced by host characteristics,and play a significant role in plant health and productivity.Nonetheless,the impact of host... Phyllosphere microorganisms are a crucial component of environmental microorganisms,highly influenced by host characteristics,and play a significant role in plant health and productivity.Nonetheless,the impact of host characteristics on shaping phyllosphere microbial communities of plants with different life forms remains ambiguous.Utilizing high-throughput sequencing technology,this study analyzed the diversity and community composition of phyllosphere epiphytic microorganisms(e.g.,bacteria and fungi)of various plant life forms in the hinterland of the Gurbantunggut Desert,Northwest China.Functional annotation of prokaryotic taxa(FAPROTAX)and fungi function guild(FUNGuild)were employed to assess the ecological functions of microorganisms and to investigate the role of stochastic and deterministic processes in shaping phyllosphere microbial communities.Result showed a diverse array of phyllosphere epiphytic microorganisms in the desert plants,with Proteobacteria,Cyanobacteria,and Actinobacteriota dominating bacterial community,while Ascomycota and Basidiomycota were prevalent in fungal community.Comparison across different plant life forms highlighted distinct microbial communities,indicating strong filtering effects by plant characteristics.FAPROTAX prediction identified intracellular parasites(accounting for 27.44%of bacterial community abundance),chemoheterotrophy(10.12%),and phototrophy(17.41%)as the main functions of epiphytic bacteria on leaves of different life form plants.FUNGuild prediction indicated that phyllosphere epiphytic fungi primarily served as Saprotrophs(81.77%),Pathotrophs(17.41%),and Symbiotrophs(0.82%).Co-occurrence network analysis demonstrated a predominance of positive correlations among different microbial taxa.Raup-Crick dissimilarity index analysis revealed that deterministic processes predominantly influenced phyllosphere bacterial and fungal community assembly.Variance partitioning analysis and random forest modeling suggested that plant leaf functional traits significantly impacted both bacterial and fungal community composition,with fungal community composition showing a closer association with leaf nutrients and physiology compared with bacterial community composition.The distinct responses of bacterial and fungal communities to plant traits were attributed to the differing properties of bacteria and fungi,such as bacteria having higher potential dispersal rates and broader ecological niches than fungi.Overall,the results indicate that phyllosphere bacterial and fungal communities undergo similar community assembly processes,with fungi being more influenced by plant characteristics than bacteria.These findings offer novel insights into the ecology of phyllosphere microbial communities of desert plants. 展开更多
关键词 phyllosphere epiphytic bacteria phyllosphere epiphytic fungi community structure community diversity functional diversity plant life form plant functional traits
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Expectations and Level of Satisfaction of the Patient with Parkinson’s Disease Undergoing Deep Brain Stimulation Surgery at the National Institute of Neurology and Neurosurgery
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作者 Paola Bazán-Rodríguez Eduardo Ichikawa-Escamilla +4 位作者 Etienne Reséndiz-Henríquez Carlos E. Martínez-Cortés Amin Cervantes-Arriaga Mayela Rodríguez-Violante Lisette Bazán-Rodríguez 《Advances in Parkinson's Disease》 CAS 2024年第1期1-7,共7页
Background: Deep brain stimulation (DBS) is an established treatment for patients with advanced Parkinson’s disease (PD). Reports show continued patient satisfaction after surgery despite not maintaining clinical imp... Background: Deep brain stimulation (DBS) is an established treatment for patients with advanced Parkinson’s disease (PD). Reports show continued patient satisfaction after surgery despite not maintaining clinical improvement as measured by evolution scales. Objectives: The present study sought to explore expectations and level of satisfaction in patients after DBS surgery with a semi-structured questionnaire and subsequent correlation with functional scales, Quality of Life (QoL), and motor and non-motor symptoms. Methods: We performed descriptive statistics to represent demographic data, Wilcoxon rank tests to determine significant differences, and Spearman correlation between the applied scales. Results: We evaluated 20 patients with a history of DBS surgery. 45% were female, with a mean age of 55.7 ± 14.15 years, a mean disease duration of 13.42 ± 8.3 years, and a mean time after surgery of 3.18 ± 1.86 years. Patients reported surgery meeting expectations in 85.5% and continued satisfaction in 92%. These two variables showed a significant correlation. Conclusions: This sample of patients remained satisfied after DBS surgery, although we found no differences in motor and non-motor clinimetric scales. Further studies are needed to confirm the importance of assessing quality of life in patients with DBS. 展开更多
关键词 Parkinson’s Disease Quality of life Deep Brain stimulation Patient satisfaction
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基于B/S架构的军校教材管理系统分析与设计
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作者 李爽 范振凯 《天津科技》 2024年第3期56-59,64,共5页
近年来,军校教材呈现爆发式增长,旧的教材管理系统已不能有效进行信息化管理,工作效率低。根据军校对教材管理的特定需求,对系统和技术可行性进行客观分析,提出一种基于B/S架构的军校教材管理系统设计,并探讨系统运行性能指标,对系统的... 近年来,军校教材呈现爆发式增长,旧的教材管理系统已不能有效进行信息化管理,工作效率低。根据军校对教材管理的特定需求,对系统和技术可行性进行客观分析,提出一种基于B/S架构的军校教材管理系统设计,并探讨系统运行性能指标,对系统的拓扑结构、运行环境、功能实现等进行全面设计,充分利用军校现有的校园网络系统实现每册教材的全生命周期管理。 展开更多
关键词 数字校园 全生命周期信息化管理 循环利用 快速追溯 B/s架构
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基于ABAQUS的汽车转向拉杆心轴疲劳失效分析及改进
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作者 叶丹 余超群 +2 位作者 刘雅琪 李纯军 左学谦 《机械管理开发》 2024年第7期11-14,共4页
转向拉杆是汽车转向机构中的重要零件,它在转向系中起着传递运动的作用,直接影响汽车操纵的稳定性、运行的安全性和轮胎的使用寿命。运用ABAQUS对某车型转向拉杆外球节心轴进行CAE分析并结合其材料的S-N曲线验证第一次根据经验设计出的... 转向拉杆是汽车转向机构中的重要零件,它在转向系中起着传递运动的作用,直接影响汽车操纵的稳定性、运行的安全性和轮胎的使用寿命。运用ABAQUS对某车型转向拉杆外球节心轴进行CAE分析并结合其材料的S-N曲线验证第一次根据经验设计出的产品的不合理性,然后通过CAE有限元分析方法设计出符合客户疲劳寿命要求的产品,并通过实验验证。 展开更多
关键词 汽车转向拉杆 疲劳寿命 CAE 心轴 s-N曲线
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朱氏滋脾固肾方Ⅰ号对慢性肾脏病2~4期脾肾气虚证症状评分、SCr及BUN的影响
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作者 费佳 马源 朱辟疆 《西部中医药》 2024年第8期111-114,共4页
目的:探讨朱氏滋脾固肾方Ⅰ号治疗慢性肾脏病(chronic kidney disease,CKD)2~4期脾肾气虚证的临床效果及对症状评分、血清肌酐(Serum creatinine,SCr)、血清尿素氮(blood urea nitrogen,BUN)等指标的影响。方法:选取CKD 2~4期患者60例,... 目的:探讨朱氏滋脾固肾方Ⅰ号治疗慢性肾脏病(chronic kidney disease,CKD)2~4期脾肾气虚证的临床效果及对症状评分、血清肌酐(Serum creatinine,SCr)、血清尿素氮(blood urea nitrogen,BUN)等指标的影响。方法:选取CKD 2~4期患者60例,依据随机数字表法分为观察组和对照组各30例。对照组采取西医常规治疗,观察组在对照组治疗基础上联合朱氏滋脾固肾方Ⅰ号治疗,两组患者均持续治疗12周,后续治疗在专科门诊随访。比较两组临床效果、症状评分、生活质量评分、肾功能指标水平(SCr、BUN)及不良反应情况。结果:观察组总有效率为86.67%(26/30),高于对照组的60.00%(18/30)(P<0.05)。治疗后两组各项症状评分、SCr及BUN水平均较治疗前下降(P<0.05),生活质量评分均上升(P<0.05),且观察组上述指标下降或上升较对照组显著(P<0.05)。两组不良反应发生率比较差异无统计学意义(P>0.05)。结论:朱氏滋脾固肾方Ⅰ号治疗CKD 2~4期脾肾气虚证患者具有显著疗效,可以改善患者肾功能及生活质量。 展开更多
关键词 肾脏病 慢性 朱氏滋脾固肾方Ⅰ号 肾功能 生活质量 临床疗效
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Functional Enrichment of Utopian Distribution of Plant Life-Forms
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作者 James N. Furze Quanmin Zhu +1 位作者 Feng Qiao Jennifer Hill 《American Journal of Plant Sciences》 2013年第12期37-48,共12页
Adaptive fuzzy neural inference systems are used to illustrate the primary nodal number of plant life-forms. Categorization of two candidate areas is carried out using the water-energy dynamic (for Ecuador, South Amer... Adaptive fuzzy neural inference systems are used to illustrate the primary nodal number of plant life-forms. Categorization of two candidate areas is carried out using the water-energy dynamic (for Ecuador, South America) and Macedonia, Southern Europe), within which the life-form spectra are distributed. Genetic optimization methods are used to expand the primary nodal number to the complete number of life-form categories. The distribution of the elements exhibits a stochastic, binomial distribution and the utopia line and curve are summarized which enhance accuracy of the climatic data and of the consequent numbers of plant species occurrences. Expansion of the distribution of each life-form category is approximated within the Z utopia hyperplane with use of the functional approximation algorithm. This process gives additional structure and informative value to the Z plane, enhancing our ability to make informed policy decisions concerning species and ecosystem conservation. 展开更多
关键词 Adaptive Neural Fuzzy Inference system PLANT life-form Genetic Optimization stochastic UTOPIA FUNCTIONAL Approximation Algorithm
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