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Response of root traits of Reaumuria soongorica and Salsola passerina to facilitation 被引量:4
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作者 haina zhang PeiXi SU +2 位作者 ShanJia LI ZiJuan ZHOU TingTing XIE 《Journal of Arid Land》 SCIE CSCD 2014年第5期628-636,共9页
C3 plant Reaumuria soongorica and C4 plant Salsola passerina are super xerophytes and coexist in a mixed community in either isolated or associated growth, and interspecific facilitation occurs in associated growth. I... C3 plant Reaumuria soongorica and C4 plant Salsola passerina are super xerophytes and coexist in a mixed community in either isolated or associated growth, and interspecific facilitation occurs in associated growth. In the present study, the root traits including root distribution, root length(RL), root surface area(RSA), root weight(RW) and specific root length(SRL) of both species in two growth forms were investigated to clarify their response to facilitation in associated growth. Six isolated plants of each species, as well as six associated plants similar in size and development were selected during the plant growing season, and their roots were excavated at 0–10, 10–20, 20–30, 30–40 and 40–50 cm soil depths at the end of the growing season. All the roots of each plant were separated into the two categories of fine roots(2 mm diameter) and coarse roots(≥2 mm diameter). Root traits such as RL and RSA in the fine and coarse roots were obtained by the root analyzing system WinRHIZO. Most of the coarse roots in R. soongorica and S. passerina were distributed in the top 10 cm of the soil in both growth forms, whereas the fine roots of the two plant species were found mainly in the 10–20 and 20–30 cm soil depths in isolated growth, respectively. However, the fine roots of both species were mostly overlapped in 10–20 cm soil depth in associated growth. The root/canopy ratios of both species reduced, whereas the ratios of their fine roots to coarse roots in RL increased, and both species had an increased SRL in the fine roots in associated growth. In addition, there was the increase in RL of fine roots and content of root N for S. passerina in associated growth. Taken together, the root growth of S. passerina was facilitated for water and nutrient exploration under the interaction of the overlapped roots in both species in associated growth, and higher SRL allowed both species to more effectively adapt to the infertile soil in the desert ecosystem. 展开更多
关键词 C3 plant C4 plant facilitation relationship root traits specific root length
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海上含H2S裸眼井测试井下工艺研究及实践
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作者 赵启彬 刘振江 +2 位作者 孙小科 张海娜 崔露 《石油天然气学报》 CAS 2018年第5期44-50,共7页
含H2S油气生产一直是油气行业的高危作业之一,裸眼的完井方式同样会给测试作业带来井控、测试液选型等一系列工程问题。含H2S裸眼井测试综合了上述两种作业的难度,对井下测试工艺要求十分苛刻。渤海油田通过对井下工具的改良和创新使... 含H2S油气生产一直是油气行业的高危作业之一,裸眼的完井方式同样会给测试作业带来井控、测试液选型等一系列工程问题。含H2S裸眼井测试综合了上述两种作业的难度,对井下测试工艺要求十分苛刻。渤海油田通过对井下工具的改良和创新使用,解决了裸眼和含H2S气体两大难题对井下工艺的影响,并通过了实践的检验,安全高效地完成了作业,形成了一套特色井下测试工艺,为以后海上平台含H2S裸眼井测试作业奠定了基础。 展开更多
关键词 海上平台 H2S 裸眼 地层测试 井下工艺
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Species diversity and its relation with soil factors under different site conditions in a desert-oasis ecotone
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作者 TingTing Xie PeiXi Su +2 位作者 ZiJuan Zhou ShanJia Li haina zhang 《Research in Cold and Arid Regions》 CSCD 2013年第3期331-338,共8页
Vegetation and soil surveys were conducted under different site conditions in 2007-2011 to study species diversity using richness, evenness and diversity indices, in the middle portion of the Heihe River Basin. The re... Vegetation and soil surveys were conducted under different site conditions in 2007-2011 to study species diversity using richness, evenness and diversity indices, in the middle portion of the Heihe River Basin. The relationship between species distribution and soil environmental factors was also studied by Canonical Correspondence Analysis (CCA). Results show that vegetation coverage and species diversity were the highest in the interdune lowland, and the lowest in the mobile dime. Results of the Hill's index (di- versity ordering) shows that species diversity is reduced along decreasing soil water content, and the order of species diversity was interdune lowland, flat slope, fixed dune, semifixed dune and mobile dune. The influence degree of soil factors on vegetation dis- tribution was soil water content 〉 pH 〉 total K 〉 organic matter 〉 available N 〉 total N 〉 available K 〉 total P 〉 saline content 〉 available P. Soil water content and pH were important factors significantly affecting spatial distribution difference of vegetation, the environmental explanation was 98%. 展开更多
关键词 desert-oasis ecotone species diversity soil factor canonical correspondence analysis
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Two new high-temperature molecular ferroelectrics[1,5-3.2.2-Hdabcn]X(X=ClO_(4)^(-),ReO_(4)^(-))
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作者 Keke Han Wenjun Rao +4 位作者 Xiuli You haina zhang Xing Ye Zhenhong Wei Hu Cai 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第6期234-238,共5页
Molecular ferroelectrics have attracted much attention because of their excellent piezoelectricity,mechanical workability,and second harmonic effect.Here,we successfully prepared two molecular ferroelectrics[1,5-3.2.2... Molecular ferroelectrics have attracted much attention because of their excellent piezoelectricity,mechanical workability,and second harmonic effect.Here,we successfully prepared two molecular ferroelectrics[1,5-3.2.2-Hdabcn]X(X=ClO_(4)^(-),1;ReO_(4)^(-),2)by reactions of a quasi-spherical amine 1,5-diazabicycle[3.2.2]nonane(1.5-3.2.2-dabcn)with HX aqueous solution.Compounds 1 and 2 undergo hightemperature phase transitions at 381 K(1)and 396 K(2).Before and after the phase transition,they crystallize in the polar point group mm2,and the centrosymmetric point groups mmm and 4/mmm,respectively.According to Aizu rules,these two compounds experience mmm Fmm2 and 4/mmm Fmm2 type ferroelectric phase transitions,respectively.The ferroelectricity of both compounds is well expressed in their polycrystalline film at room temperature with low coercive voltages of 13 V for 1 and 25 V for 2.Using piezoelectric force microscopy(PFM),the 180°anti-parallel ferroelectric domains and the reversible polarization switching can be clearly observed in 1 and 2.This high-temperature molecular ferroelectric material has great application potential in flexible materials,biomechanics,intelligent wearables and other fields. 展开更多
关键词 Ferroelectric domains Quasi-spherical amine Phase transition Polarization
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北京6个城区社区全科医生痴呆管理能力现况调查及相关因素分析 被引量:2
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作者 张海娜 李婧 +1 位作者 陈小垒 杜娟 《中华全科医师杂志》 2022年第11期1043-1049,共7页
目的了解北京市6个城区社区全科医生痴呆管理能力现况, 为提升全科医生痴呆管理能力提供建议, 为今后开展相关管理提供参考。方法自行设计社区全科医生痴呆管理能力问卷, 内容包括全科医生的一般情况和痴呆管理能力自评问卷两部分。于2... 目的了解北京市6个城区社区全科医生痴呆管理能力现况, 为提升全科医生痴呆管理能力提供建议, 为今后开展相关管理提供参考。方法自行设计社区全科医生痴呆管理能力问卷, 内容包括全科医生的一般情况和痴呆管理能力自评问卷两部分。于2018年7月1日至11月30日, 采用二阶段抽样方法, 在北京市城六区每区按20%的比例简单随机抽样, 共抽取27家社区卫生服务中心, 对其中符合纳排标准的479名全科医生进行在线调查, 采用SPSS 20.0 对数据进行多重线性回归分析。结果社区全科医生痴呆管理能力整体得分(53.9±10.3)分;"痴呆诊断前的发现、评估和转诊"维度得分(25.5±5.1)分, 其中条目"对可疑痴呆患者建议转诊"得分最高, 为(4.1±0.8)分, "使用神经精神问卷(NPI-Q)进行精神行为症状评估"得分最低, 为(3.4±1.0)分;"痴呆诊断后的治疗及管理"维度得分(28.4±6.2)分, 其中条目"提供关于提升痴呆患者安全的指导"得分最高, 为(3.7±0.9)分, "提供关于改善痴呆患者认知功能的非药物指导"得分最低, 为(3.4±1.0)分。多重线性回归结果显示, 对痴呆社区管理的态度(B=0.30, t=0.69, P<0.01)和近1年接受痴呆相关培训(B=1.38, t=2.18, P<0.05)是"痴呆诊断前的发现、评估和转诊"维度的相关因素, 对痴呆社区管理的态度(B=0.47, t=9.17, P<0.01)是"痴呆诊断后的治疗及管理"维度的相关因素。结论社区全科医生自感痴呆管理能力不足, 接受过痴呆培训、态度越积极的社区全科医生痴呆管理能力越高, 需加相关培训提高全科医生痴呆管理工作积极性和管理能力。 展开更多
关键词 社区卫生服务 痴呆 问卷调查 管理 全科医生
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Contextualizing Transformational Leadership Theories in China: A Confucian Perspective 被引量:2
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作者 haina zhang Malcolm H. Cone +1 位作者 Andre M. Everett Graham Elkin 《Frontiers of Business Research in China》 2013年第2期189-218,共30页
Transformational leadership, though widely studied in the literature, lacks sufficient contextual analysis of its essential leadership process and differences in characteristic behaviors under different cultural setti... Transformational leadership, though widely studied in the literature, lacks sufficient contextual analysis of its essential leadership process and differences in characteristic behaviors under different cultural settings, especially in the Asian context. This research, through qualitative data collected from eight Chinese organizations (four state-owned enterprises and four private-owned enterprises), empirically examines the Western transformational leadership theory in China. Moreover, by studying Chinese leaders' daily behaviors, we develop a transformational leadership theory in the Chinese business context. This research contributes to contextualizing transformational leadership behaviors and providing deep insights into the Chinese transformational leadership process from a philosophical perspective. Findings can be applied to both Chinese and Western management studies as well as the World of business practice. 展开更多
关键词 China CONFUCIANISM transformational leadership
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Complexity absorption: a processual strategic approach to corporate entrepreneurship strategy 被引量:1
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作者 haina zhang 《Frontiers of Business Research in China》 2017年第3期374-399,共26页
In contrast to traditional strategic approaches that are based on complexity reduction, this paper aims to develop an alternative way of understanding entrepreneurial strategy and managing complexity from a processual... In contrast to traditional strategic approaches that are based on complexity reduction, this paper aims to develop an alternative way of understanding entrepreneurial strategy and managing complexity from a processual perspective. The new perspective is developed from a processual perspective integrating insights from an understanding of complexity to engage with philosophical accounts of Chinese processual thought particularly as it is applied to entrepreneurial strategy. The new theoretical framework is empirically investigated through case studies of 30 entrepreneurial organizations in China. The findings confirm that timing and action, context/situation, and efficacy are the three key components in complexity absorption as preferred entrepreneurial strategic approaches. 展开更多
关键词 Complexity absorption Entrepreneurial strategy Chinese processual philosophy
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