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Plant water use strategies in the Shapotou artificial sand-fixed vegetation of the southeastern margin of the Tengger Desert, northwestern China

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Journal of Mountain Science 2019年第4期16卷 898-908页

作者： ZHAO Liang-ju WANG Xiao-gang ZHANG yu-cui XIE Cong liu quan-yu MENG Fei Key Laboratory of Earth Surface System and Environmental Carrying Capacity College of Urban and Environmental Sciences Northwest University Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Key Laboratory of Agricultural Water Resources Center for Agricultural Resources Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences College of Tourism and Environment Ankang University

Stable oxygen and hydrogen isotopic compositions(δ^(18)O and δD) of plant xylem water and its potential water sources can provide new information for studying water sources, competitive interactions and water use patterns of plants. The contributions of different water sources to three plants, Hedysarum scoparium(HS), Caragana Korshinskii(CK) and Artemisia ordosica(AO), were investigated in the artificial sand-fixed vegetation of Shapotou, the southeastern margin of the Tengger Desert of northwestern China, based on meteorological data and δ^(18)O and δD values of precipitation, groundwater, soil water and xylem water of HS, CK and AO. Our results indicated that soil water infiltration through precipitation was the main water source of the artificial sand-fixed vegetation. Obvious differences in soil water content and in δ^(18)O of soil water and xylem water were found among different seasons. No relationship was found between the δ^(18)O in plant xylem water and in soil water in January. The same water use patterns were found in CK, HS and AO in May, suggesting they have the same water sources. The different water sources of CK, HS and AO in August indicate that water competition occurred. In addition, the main water sources of CK, HS and AO in August mainly come from shallow soil water, while they use relatively deep soil water in May. This phenomenon is related to the differences of soil water content throughout soil profile, precipitation, transpiration and water competition under different growth periods. The water use patterns of CK, HS and AO respond to soil water content throughout the soil profile and their competition balance for water uptake during different growth season. The results indicate that these sandfixed plants have developed into a relatively stable stage and they are able to regulate their water use behavior as a response to the environmental conditions, which reinforces the effectiveness of plantation of native shrubs without irrigation in de

关键词： Plant water source Stable hydrogen and oxygen isotopes Artificial and sand-fixed vegetation in Shapotou

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Traditional Use,Phytochemistry,Pharmacology,Toxicology and Clinical Applications of Persicae Semen:A Review

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Chinese Journal of Integrative Medicine 2024年第12期30卷 1137-1147页

作者： liu yu-quan WU Hui-li ZHANG Zhi-qiang WANG Wen-le HAN Guo-qing ZHANG Chun-hong Lyu Xin-liang MA Chun-jie LI Min-hui School of Traditional Chinese Medicine Inner Mongolia Medical UniversityHohhot 010000China Department of Rheumatology Inner Mongolia Autonomous Region Hospital of Traditional Chinese MedicineHohhot 010020China School of Pharmacy Baotou Medical CollegeBaotou 014040China Infectious Disease Department Hohhot Mongolian Medicine of Traditional Chinese Medicine HospitalHohhot 010000China

Persicae Semen(Taoren),the seed of mature peaches consumed as both food and medicine,is native to the temperate regions of China,distributed in the provinces of North and East China,and currently cultivated *** primary components of Persicae Semen include volatile oil,protein,amino acids,amygdalin,and prunasin,all of which have pharmacological properties,such as anti-inflammatory,antioxidant,and immune regulatory effects,and are clinically used in the treatment of gynecological,cardiovascular,cerebrovascular,orthopedic,and digestive system *** review provides a comprehensive perspective on the resource status,ethnopharmacology,phytochemistry,pharmacology,and toxicology,as well as the trend of Persicae Semen patent,global distribution,and clinical *** review will help facilitate the development and utilization of Persicae Semen in clinical settings.

关键词： Persicae Semen phamacology clinical applications food-medicine homology phytochemistry review

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SYNTHESIS OF DBN AND ITS CATALYTIC PERFORMANCE FOR METHANOL CARBONYLATION TO METHYL FORMATE

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Journal of Energy Chemistry 1995年第1期 119-127页

作者： liu Xing-quan WU yu-Tang JIA Zhao-XiaChengdu Institute uf Organic ChemistryAcademia SinicaChengdu, Sichuan 610015 To whom correspondence should be addressed.

1 , 5-diazabicyclo[’1, 3, 0]non-5-ene(DBN) has been synthesized in our laboratory, and its catalytic activity and selectivity for methanol carbonylation to methyl formate (MF) have been studied. The experimental results have demonstrated that the synthetic processes of DBN used for the present work are reasonable and feasible. The total yield of three steps of DBN synthsis is approximate to 80%. The activity evaluation has shown that DBN can effectively catalyze the carbonylation reaction of methanol in the presence of propylene oxide (PO) promoter. PO-promoted DBN is a novel catalytic system superior to sodium methoxide.

关键词： synthesis of DBN DBN catalyst methanol carbonylation methyl formate propylene oxide promoter

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Gamma-Gamma大气湍流中部分相干光通信系统性能研究

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红外与激光工程 2017年第3期46卷 138-144页

作者：吴君鹏刘泉于林韬长春理工大学电子信息工程学院吉林长春130022 东北电力大学电气工程学院吉林吉林132012 长春理工大学光电工程学院吉林长春130022

部分相干光在湍流大气中传输时,可以有效抑制湍流所引起的光强闪烁效应,从而改善通信链路性能。针对Gamma-Gamma大气湍流信道模型和部分相干光的光束特性,得到了采用OOK调制方式下部分相干光通信系统的平均误码率、中断概率和平均信道... 详细信息

部分相干光在湍流大气中传输时,可以有效抑制湍流所引起的光强闪烁效应,从而改善通信链路性能。针对Gamma-Gamma大气湍流信道模型和部分相干光的光束特性,得到了采用OOK调制方式下部分相干光通信系统的平均误码率、中断概率和平均信道容量三个性能指标的解析表达式;在此基础上,分析了光束的空间相干长度和通信距离对通信链路的性能影响。计算结果表明,在相同的大气湍流条件和传输距离下,随着部分相干光的空间相干长度的减小,系统的误码率和中断概率逐步降低,在平均信噪比为30 dB时,系统的误码率可以达到10^(-5),中断概率低于10^(-6);另外,系统的平均信道容量会随着光束相干长度的减小而增加,在信噪比等于12 dB时,平均信道容量达到3.8 b/s·Hz^(-1)。分析结果为部分相干光在湍流大气中实现可靠通信提供了理论依据。

关键词：部分相干光光强闪烁误码率中断概率平均信道容量

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MXene Hybridized Polymer with Enhanced Electromagnetic Energy Harvest for Sensitized Microwave Actuation and Self-Powered Motion Sensing

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NANO-MICRO LETTERS 2025年第1期17卷 1-15页

作者： Wang, yu-Ze Wang, yu-Chang liu, Ting-Ting Zhao, quan-Liang Li, Chen-Sha Cao, Mao-Sheng Beijing Inst Technol Sch Mat Sci & Engn Beijing 100081 Peoples R China Peking Univ Sch Mat Sci & Engn Beijing 100871 Peoples R China North China Univ Technol Sch Mech & Mat Engn Beijing 100144 Peoples R China Heilongjiang Univ Minist Educ Peoples Republ China Key Lab Funct Inorgan Mat Chem Harbin 150080 Peoples R China

Polymeric microwave actuators combining tissue-like softness with programmable microwave-responsive deformation hold great promise for mobile intelligent devices and bionic soft robots. However, their application is challenged by restricted electromagnetic sensitivity and intricate sensing coupling. In this study, a sensitized polymeric microwave actuator is fabricated by hybridizing a liquid crystal polymer with Ti3C2Tx (MXene). Compared to the initial counterpart, the hybrid polymer exhibits unique space-charge polarization and interfacial polarization, resulting in significant improvements of 230% in the dielectric loss factor and 830% in the apparent efficiency of electromagnetic energy harvest. The sensitized microwave actuation demonstrates as the shortened response time of nearly 10 s, which is merely 13% of that for the initial shape memory polymer. Moreover, the ultra-low content of MXene (up to 0.15 wt%) benefits for maintaining the actuation potential of the hybrid polymer. An innovative self-powered sensing prototype that combines driving and piezoelectric polymers is developed, which generates real-time electric potential feedback (open-circuit potential of similar to 3 mV) during actuation. The polarization-dominant energy conversion mechanism observed in the MXene-polymer hybrid structure furnishes a new approach for developing efficient electromagnetic dissipative structures and shows potential for advancing polymeric electromagnetic intelligent devices.

关键词： Microwave absorption Electromagnetic response Energy harvest Self-sensing Soft actuator

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智能配电网技术支持系统的研究与应用

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电力系统保护与控制 2010年第21期38卷 162-166,172页

作者：吴国沛刘育权广东电网公司广州供电局调通中心广东广州510630 华南理工大学电力学院广东广州510630

智能配电网通过网络技术和智能控制技术提高能源利用效率和能源供应安全性,提高配电网智能化水平和供电可靠性。结合智能配电网技术发展和地区电网配网自动化系统建设,研究智能配电网技术支持系统的关键技术。介绍地区电网在智能配电网... 详细信息

智能配电网通过网络技术和智能控制技术提高能源利用效率和能源供应安全性,提高配电网智能化水平和供电可靠性。结合智能配电网技术发展和地区电网配网自动化系统建设,研究智能配电网技术支持系统的关键技术。介绍地区电网在智能配电网部分关键技术中的研究和实施情况,对包括基于地理信息系统的配电自动化系统建设、基于实时全景信息的配网智能调度运行技术和基于实时数据库的配网数据挖掘技术等关键技术进行分析。对建设试点工作情况和存在问题进行介绍,对智能配电网的建设具有借鉴意义。

关键词：智能配电网技术支持系统配网自动化

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Interconnections between diabetic corneal neuropathy and diabetic retinopathy:diagnostic and therapeutic implications

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Neural Regeneration Research 2025年第8期20卷 2169-2180页

作者： Mingyi yu Faith Teo En Ning Chang liu yu-Chi liu Tissue Engineering and Stem Cell Group Singapore Eye Research InstituteSingapore Yong Loo Lin School of Medicine National University of SingaporeSingapore Department of Cornea and External Eye Disease Singapore National Eye CenterSingapore Ophthalmology and Visual Sciences Academic Clinical Program Duke-NUS Medical SchoolSingapore

Diabetic corneal neuropathy and diabetic retinopathy are ocular complications occurring in the context of diabetes *** corneal neuropathy refers to the progressive damage of corneal *** retinopathy has traditionally been considered as damage to the retinal ***,growing evidence suggests that diabetic retinopathy is a complex neurovascular disorder resulting from dysfunction of the neurovascular unit,which includes both the retinal vascular structures and neural *** retinopathy is one of the leading causes of blindness and is frequently screened for as part of diabetic ocular ***,diabetic corneal neuropathy is commonly overlooked and underdiagnosed,leading to severe ocular surface *** studies have found that these two conditions tend to occur together,and they share similarities in their pathogenesis pathways,being triggered by a status of chronic *** review aims to discuss the interconnection between diabetic corneal neuropathy and diabetic retinopathy,whether diabetic corneal neuropathy precedes diabetic retinopathy,as well as the relation between the stage of diabetic retinopathy and the severity of corneal *** also endeavor to explore the relevance of a corneal screening in diabetic eyes and the possibility of using corneal nerve measurements to monitor the progression of diabetic retinopathy.

关键词： cornea corneal nerves diabetes diabetic corneal neuropathy diabetic retinopathy retina

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红花桑寄生中的化学成分（英文）

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中国中药杂志 2016年第21期41卷 3956-3961页

作者：刘全裕冯珊张永红倪峰福建卫生职业技术学院药学系福建福州350101 福建医科大学药学院福建福州350004

从红花桑寄生茎叶中分离得到1个新的化合物为7β-羟基-何帕-22（29）-烯-3β-棕榈酸酯（1）,以及9个已知化合物,分别鉴定为熊果醇（2）、3-表乌苏酸（3）、3β-羟基-何帕-22（29）-烯（4）、3β,15α-二羟基-羽扇-20（29）-烯（5）、羽... 详细信息

从红花桑寄生茎叶中分离得到1个新的化合物为7β-羟基-何帕-22（29）-烯-3β-棕榈酸酯（1）,以及9个已知化合物,分别鉴定为熊果醇（2）、3-表乌苏酸（3）、3β-羟基-何帕-22（29）-烯（4）、3β,15α-二羟基-羽扇-20（29）-烯（5）、羽扇-20（29）-烯-3-O-α-D-葡萄糖苷（6）、豆甾醇-3-O-β-D-葡萄糖苷（7）、夹竹桃苷元-3-O-α-D-葡萄糖苷（8）、二十二烷酸（9）、二十八烷醇（10）。化合物结构利用核磁共振谱、高分辨质谱等现代波普技术进行鉴定。化合物1为新化合物,化合物2~10首次从红花桑寄生中分离得到。

关键词：红花桑寄生化学成分三萜酯

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优化课堂教学环境的研究

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中国教育学刊 2005年第6期 32-34页

作者：彭贤智刘玉娟唐山师范学院河北唐山063000

创设参与的教学环境,让学生主动学习;创设丰富的信息资源环境,让学生在优化的情境中学习;创设知识经验共享环境,让学生在协作中学习;创设真实环境,让学生在体验中学习。通过上述方式优化课堂教学环境,使学生的学习成为有效学习。

关键词：主动学习情境中学习协作中学习体验中学习

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Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun liu Yiren yu Guoshu Gao yumeng Zhao Xiongfu Zhang Guodong liu Guohui Yang State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation

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