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Zeeman effects on Josephson current in d-wave superconductor/d-wave superconductor junctions
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作者 廖艳华 董正超 +1 位作者 尹在峰 付浩 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第5期1893-1901,共9页
This paper solves a self-consistent equation for the d-wave superconducting gap and the effective exchange field in the mean-field approximation, and studies the Zeeman effects on the d-wave superconducting gap and th... This paper solves a self-consistent equation for the d-wave superconducting gap and the effective exchange field in the mean-field approximation, and studies the Zeeman effects on the d-wave superconducting gap and thermodynamic potential. The Josephson currents in the d-wave superconductor(S)/insulating layer(I)/d-wave S junctions are calculated as a function of the temperature, exchange field, and insulating barrier strength under a Zeeman magnetic field on the two d-wave Ss. It is found that the Josephson critical currents in d-wave S/d-wave S junction to a great extent depend on the relative orientation of the effective exchange field of the two S electrodes, and the crystal orientation of the d-wave S. The exchange field under certain conditions can enhance the Josephson critical current in a d-wave S/I/d-wave S junction. 展开更多
关键词 Zeeman effect d-wave s/d-wave s ferromagnetic d-wave superconductor Josephson current
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Verification of the Physiological Therapeutic Effects of Harvesting Activities in a Patient with Moderate Alzheimer’s Disease with Long-Term Agricultural Experience
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作者 Kikuo Eguchi Seigo Koura +1 位作者 Nao Eguchi Akihiko Kondou 《Open Journal of Therapy and Rehabilitation》 2024年第3期236-244,共9页
Background: Harvesting activities have proven effective in reducing stress in patients with dementia. At a psychiatric hospital, occupational therapists (OT) made patients with dementia perform vegetable harvesting ac... Background: Harvesting activities have proven effective in reducing stress in patients with dementia. At a psychiatric hospital, occupational therapists (OT) made patients with dementia perform vegetable harvesting activities as a part of their treatment. The patients became calmer and began to smile not only after but also before and during harvesting activity. Therefore, this study aimed to measure autonomic nervous system (ANS) responses over time in a female patient in her 80s with moderate Alzheimer’s disease (AD) who had experience in farming when performing harvesting activities. Additionally, this study aimed to consider factors associated with changes in ANS responses over time and to verify the physiological therapeutic effects of harvesting activities. Methods: An OT with more than 10 years of experience and a good relationship with the patient conducted one-on-one sessions with the patient. Harvesting activity was performed in a courtyard with trees. The patient harvested lettuce (three lettuce plants) grown in a planter while sitting on a chair. Additionally, the planter was set up on a desk. ANS responses were measured over time from before to after the activity for different events at six time periods. Changes in the patient’s ANS responses were assessed during each period. Results: With the involvement of environmental factors and OT during harvesting activities, parasympathetic nervous system (PNS) activity significantly increased. This may lead to improved mental stability. Conclusion: The findings of this study indicate that implementing harvesting activities may have a positive effect on the PNS in patients with AD with long-term agricultural experience. However, further studies with a larger sample size and multidimensional evaluations are needed. 展开更多
关键词 Alzheimer’s Disease Autonomic Nervous Response Harvesting Activity Therapeutic effects
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Study on Application Effect of 6S Management Mode in Infection Control Management of Fangcang Shelter Hospital of National Exhibition and Convention Center 被引量:1
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作者 Ting Sun Jing Feng +3 位作者 Ning Han Ni Li Zhi Zan Dongxian Zhang 《Journal of Clinical and Nursing Research》 2022年第5期84-93,共10页
Objective:In 2022,a pneumonia caused by novel coronavirus broke out in Shanghai.A large number of medical personnel were deployed nationwide to support the Fangcang Shelter Hospital of National Exhibition and Conventi... Objective:In 2022,a pneumonia caused by novel coronavirus broke out in Shanghai.A large number of medical personnel were deployed nationwide to support the Fangcang Shelter Hospital of National Exhibition and Convention Center(Shanghai).Because the of the underdeveloped infrastructure and the disorganized layout process,the phenomenon of infection among medical personnel was rampant given the highly contagious nature of the Omicron variant.This paper discusses the effect of 6S management in infection control management of Fangcang Shelter Hospital of National Exhibition and Convention Center(Shanghai).Methods:A series of 6S management practices were carried out based on the evaluation of the control management of Fangcang Shelter Hospital of National Exhibition and Convention Center(Shanghai)during the anti-epidemic period,and the effect of the implementation of 6S management was studied based on the rapport among team members and the overall control system process,the management of wearing and stripping channels,the time of wearing protective articles and the psychological and emotional changes of the team members.Results:After the implementation of 6S management mode,the management of dressing room,epidemic prevention materials,and occupational protection awareness and infection control safety were significantly improved.More than 95.5%of the team members believed that improving the working environment in the shelter increased the confidence of victory in the fight against the epidemic,reduced the preparations before entering and leaving the cabin,improved the work efficiency and ensured occupational safety.It ensures the realization of the goal of“zero infection”and is set as a benchmark of control work of Fangcang Shelter Hospital of National Exhibition and Convention Center(Shanghai).Conclusion:The application of 6S management mode to the shelter infection control management can create and maintain a good working environment in the shelter,promote the implementation effect of various systems and processes of infection control,reduce the potential infection risk in the shelter and improve the efficiency of infection control management. 展开更多
关键词 Mobile cabin hospital Infection control management 6s management Application effect
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A Record of Anthropogenic Effects on Sedimentation in the Manatee River, Florida
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作者 Patrick Schwing Ashanti Johnson 《Journal of Environmental Science and Engineering(B)》 2014年第1期1-13,共13页
Increased sedimentation rates have been attributed to increased anthropogenic activity in watersheds throughout Florida and many parts of the world. The Manatee River, located on the west coast of Florida (USA), lik... Increased sedimentation rates have been attributed to increased anthropogenic activity in watersheds throughout Florida and many parts of the world. The Manatee River, located on the west coast of Florida (USA), like many other coastal watersheds, has experienced depletion in natural resources, increased nutrient loading, and increased pollution. LARs (linear accumulation rates) from watersheds throughout Florida suggest that anthropogenic activity increased bulk sedimentation by as much as 4-fold. The objective of this study was to construct a record of sedimentation and improve upon previous studies by determining individual sedimentary constituent MARs (mass accumulation rates) based on short lived radioisotopes (2~~pb and 234Th) to characterize changes in sedimentation attributed to increased anthropogenic development. This study constructed records of sedimentary accumulation rates to compare pre-development records to the past 100 years of anthropogenic development and identified specific changes in sedimentation attributed to anthropogenic activity. Anthropogenic development increased deposition of terrigenous material into the river from 2-fold to I 0-fold (0.3-2.0 g/cm2/yr) over three periods: (1) predevelopment period (1900-1941); (2) agricultural development period (1941-1970); (3) urban development period (1970-2010). The mobilization of this amount of terrigenous material has implications for effects on water quality and biological communities within the river. 展开更多
关键词 sEDIMENTATION lead-210 cesium-13 7 man induced effects Florida Tampa Bay.
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Analysis of Effect of Zn(O,S) Buffer Layer Properties on CZTS Solar Cell Performance Using AMPS
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作者 林灵燕 邱羽 +1 位作者 张禹 张昊 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第10期116-119,共4页
The Cu2ZnSnS4 (CZTS)-based solar cell is numerically simulated by a one-dimensional solar cell simulation soft- ware analysis of microelectronic and photonic structures (AMPS-1D). The device structure used in the ... The Cu2ZnSnS4 (CZTS)-based solar cell is numerically simulated by a one-dimensional solar cell simulation soft- ware analysis of microelectronic and photonic structures (AMPS-1D). The device structure used in the simulation is Al/ZnO:Al/nZn(O,S)/pCZTS/Mo. The primary motivation of this simulation work is to optimize the composition in the ZnO1-xSx buffer layer, which would yield higher conversion efficiency. By varying S/(S+O) ratio x, the conduction band offset (CBO) at CZTS/Zn(O,S) interface can range from -0.23 eV to 1.06eV if the full range of the ratio is considered. The optimal CBO of 0.23eV can be achieved when the ZnO1-xSx buffer has an S/(S+O) ratio of 0.6. The solar cell efficiency first increases with increasing sulfur content and then decreases abruptly for x〉 0.6, which reaches the highest value of 17.55% by our proposed optimal sulfur content x= 0.6. Our results provide guidance in dealing with the ZnO1-xSx buffer layer deposition for high efficiency CZTS solar cells. 展开更多
关键词 of in is CZTs O s Analysis of effect of Zn Buffer Layer Properties on CZTs solar Cell Performance Using AMPs on
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The Wolf Is Coming?——Multinationals's Entry and Effect on China's Manufacturing Industry
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作者 Xie Jing Master Erasmus University of Rotterdam,the Netherland 《China's Foreign Trade》 2008年第14期30-32,共3页
Nowadays,China has become the country that introduces the largest amount of foreign capital.Up to June 2008,the accumulative total number of foreign- invested enterprises in China is over 632 thousand:the total amount... Nowadays,China has become the country that introduces the largest amount of foreign capital.Up to June 2008,the accumulative total number of foreign- invested enterprises in China is over 632 thousand:the total amount of actual use of foreign capital is over US$582 billion.There are over 400 multination- als of top 500 investing in China,30 of which set up regional headquarters。 展开更多
关键词 Pro In The Wolf Is Coming Multinationalss Entry and effect on China’s manufacturing Industry Uss
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Robust Resource Management Control for CO2 Emission and Reduction of Greenhouse Effect: Stochastic Game Approach
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作者 Bor-Sen Chen Ying-Po Lin 《Journal of Environmental Protection》 2011年第9期1172-1191,共20页
With the increasingly severe global warming, investments in clean technology, reforestation and political action have been studied to reduce CO2 emission. In this study, a nonlinear stochastic model is proposed to des... With the increasingly severe global warming, investments in clean technology, reforestation and political action have been studied to reduce CO2 emission. In this study, a nonlinear stochastic model is proposed to describe the dynamics of CO2 emission with control inputs: clean technology, reforestation and carbon tax, under stochastic uncertainties. For the efficient resources management, a robust tracking control is designed to force resources tracking a desired reference output. The worst-case effect of stochastic parametric fluctuations, external disturbances and uncertain initial conditions on the tracking performance is considered and minimized from the dynamic game theory perspective. This stochastic game problem, in which one player (stochastic uncertainty) maximizes the tracking error and another player (control input) minimizes the tracking error, could be equivalent to a robust minimax tracking problem. To avoid solving the HJI, a fuzzy model is proposed to approximate the nonlinear CO2 emission model. Then the nonlinear stochastic game problem could be easily solved by fuzzy stochastic game approach via LMI technique. 展开更多
关键词 CO2 Emission system Dynamic GAME Theory GREENHOUsE effect LMI REsOURCE management CONTROL ROBUsT Tracking CONTROL T-s Fuzzy Model
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Effect of stress on microstructures of creep-aged 2524 alloy 被引量:3
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作者 权力伟 赵刚 +1 位作者 田妮 黄明丽 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第8期2209-2214,共6页
Microstructures of creep-aged 2524 (A1-4.3Cu-1.5Mg) aged at 170 ℃ with various stresses (0, 173 and 250 MPa) were studied on a creep machine. Ageing hardness curves under various stresses were plotted and the cor... Microstructures of creep-aged 2524 (A1-4.3Cu-1.5Mg) aged at 170 ℃ with various stresses (0, 173 and 250 MPa) were studied on a creep machine. Ageing hardness curves under various stresses were plotted and the corresponding microstructures were characterized by transmission electron microscopy (TEM). The results show that the value of peak hardness is increased, while the time to reach the peak hardness is reduced under an external stress. Meanwhile, the length of S(Al2CuMg) phase is shorter and the number density of S phases is larger in the creep-aged alloy. The predominant contribution to the peak hardness can be ascribed to the GPB zones with an elastic stress. 展开更多
关键词 creep-age s phase GPB zone hardness DIsLOCATION stress orientation effect
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Sim Man 3G模拟人在心内科危重疾病教学中的应用评价 被引量:2
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作者 梁春宇 李春峰 +2 位作者 鲍红光 张红岩 肖章博 《中国卫生产业》 2019年第10期6-8,共3页
目的 Sim Man 3G模拟人作为传统授课方法的辅助教学方法应用于心内科危重疾病的临床带教,分析探讨其应用的可行性及效果。方法将该院2015级临床本科学生100名随机分为对照组(50名)和实验组(50名),对照组使用传统教学方法,实验组在传统... 目的 Sim Man 3G模拟人作为传统授课方法的辅助教学方法应用于心内科危重疾病的临床带教,分析探讨其应用的可行性及效果。方法将该院2015级临床本科学生100名随机分为对照组(50名)和实验组(50名),对照组使用传统教学方法,实验组在传统教学方法基础之上使用Sim Man3G模拟人法进行教学,比较两组理论考试和操作技能成绩,采用问卷调查比较学生对各种教学方法的评价。结果实验组学生理论考试、操作技能成绩、学习能力及满意度均高于对照组(P<0.05)。结论应用Sim Man 3G模拟人辅助教学能够显著提高心内科危重疾病的教学效果,有助于激发学生学习兴趣,深受学生好评,值得进一步广泛推广。 展开更多
关键词 sIM man 3G 心内科 教学方法 效果评价
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甘肃积石山 M_(s)6.2级地震的震害特征与启示 被引量:6
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作者 王丽丽 王兰民 +5 位作者 卢育霞 许世阳 夏晓雨 盖海龙 池佩红 郭梅 《世界地震工程》 北大核心 2024年第1期58-71,共14页
2023年12月18日,甘肃省临夏回族自治州积石山保安族东乡族撒拉族自治县(35.70°N,102.79°E)发生了6.2级地震,震中烈度为VIII度。地震发生后,通过实地烈度评估与科学考察,对震区VI~VIII度区不同建(构)筑物与生命线工程的震害特... 2023年12月18日,甘肃省临夏回族自治州积石山保安族东乡族撒拉族自治县(35.70°N,102.79°E)发生了6.2级地震,震中烈度为VIII度。地震发生后,通过实地烈度评估与科学考察,对震区VI~VIII度区不同建(构)筑物与生命线工程的震害特点进行了统计分析;从抗震设计与施工管理、场地放大效应与地震次生灾害对建筑结构抗震性能的影响等角度,提出了此次地震的震害启示。结果表明:1)严重破坏和毁坏的建筑结构主要集中在老旧的土木结构、砖木结构和无设防或设防不规范的砖混结构。2)造成建筑结构破坏的主要原因是少量自建房抗震设计和施工的不规范、场地放大效应和地震次生灾害。3)优化和改良生土砌筑材料,改进纵横墙间的拉结措施,强化结构整体性是提高土木结构抗震的有效方法;普及“上下圈梁与构造柱”等基本抗震设防措施,规范水泥砂浆强度,提升农村工匠的施工水平,可有效提高砌体结构的整体性,避免房屋出现整体性垮塌;室内洗手间的墙体应该与房顶、纵横墙间建立有效联接,提高结构的抗震性能。4)孤突斜坡、河流高阶地与岸边为抗震不利地带。当建造用地极为匮乏,不得不选址在这些场地之上时,应该综合考虑场地的地形地貌特征、岩土体物理力学特性、水文地质条件、抗震设防目标、建筑结构类型等影响因素,做好地震灾害风险评估,根据评估结果进行科学设防。灾后重建过程中,应由政府统一规划选址、统一设计,规范施工。 展开更多
关键词 积石山6.2级地震 震害调查 场地放大效应 黄土液化流滑 震害特征
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Pretreatment with Rhodiola Rosea Extract Reduces Cognitive Impairment Induced by Intracerebroventricular Streptozotocin in Rats: Implication of Anti-oxidative and Neuroprotective Effects 被引量:15
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作者 PETER CHUNG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第4期318-326,共9页
Objective To investigate the pretreatment effects of Rhodiola rosea (R. rosea) extract on cognitive dysfunction, oxidative stress in hippocampus and hippocampal neuron injury in a rat model of Alzheimer's disease ... Objective To investigate the pretreatment effects of Rhodiola rosea (R. rosea) extract on cognitive dysfunction, oxidative stress in hippocampus and hippocampal neuron injury in a rat model of Alzheimer's disease (AD). Methods Male Sprague-Dawley rats were pretreated with R. rosea extract at doses of 1.5, 3.0, and 6.0 g/kg for 3 weeks, followed by bilateral intracerebroventricular injection with streptozotocin (1.5 mg/kg) on days 1 and 3. Behavioral alterations were monitored after 2 weeks from the lesion using Morris water maze task. Three weeks after the lesion, the rats were sacrificed for measuring the malondialdehyde (MDA), glutathione reductase (GR) and reduced glutathione (GSH) levels in hippocampus and histopathology of hippocampal neurons. Results The MDA level was significantly increased while the GR and GSH levels were significantly decreased with striking impairments in spatial learning and memory and severe damage to hippocampal neurons in the model rat induced by intracerebroventricular injection of streptozotocin. These abnormalities were significantly improved by pretreatment with R. rosea extract (3.0 g/kg). Conclusion R. rosea extract can protect rats against cognitive deficits, neuronal injury and oxidative stress induced by intracerebroventricular injection of streptozotocin, and may be used as a potential agent in treatment of neurodegenerative diseases such as AD. 展开更多
关键词 Rhodiola rosea Oxidative stress Neuroprotective effect Learning and memory Alzheimer's disease Intracerebroventricular streptozotocin
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Effect of Friedel's salt on strength enhancement of stabilized chloride saline soil 被引量:6
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作者 CHENG Yin LI Zhan-guo +1 位作者 HUANG Xin BAI Xiao-hong 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第4期937-946,共10页
In the field of soil stabilization, only calcium silicate hydrate(CSH) and ettringite(AFt) as hydration products have been reported to directly contribute to the strength enhancement of the soil. A chloride dredger fi... In the field of soil stabilization, only calcium silicate hydrate(CSH) and ettringite(AFt) as hydration products have been reported to directly contribute to the strength enhancement of the soil. A chloride dredger fill, an artificial chloride saline soil, and a non-saline soil were stabilized by Portland cement(PC) and PC with Ca(OH)_2(CH) with different contents. A series of unconfined compressive strength(UCS) tests of stabilized soil specimen after curing for 7 d and 28 d were carried out, and the hydration products and microstructure of the specimens were observed by X-ray diffractometry(XRD), scanning electronic microscopy(SEM), and energy-dispersive X-ray analysis(EDXA). The results showed that the strengths of PC+CH-stabilized chloride saline soils were much higher than those of PC-stabilized soils. A new hydration product of calcium aluminate chloride hydrate, also known as Friedel's salt, appeared in the PC+CH-stabilized chloride saline soils. The solid-phase volume of Friedel's salt expanded during the formation of the hydrate; this volume filled the pores in the stabilized soil. This pore-filling effect was the most important contribution to the significantly enhanced strength of the PC+CH-stabilized chloride saline soils. On the basis of this understanding, a new optimized stabilizer was designed according to the concept that the chloride in saline soil could be utilized as a component of the stabilizer. The strength of the chloride saline soils stabilized by the optimized stabilizer was even further increased compared with that of the PC+CH-stabilized soils. 展开更多
关键词 CHLORIDE sALINE sOIL sTABILIZED sOIL Friedel’s sALT strength enhancement effect
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Lactoferrin modification of berberine nanoliposomes enhances the neuroprotective effects in a mouse model of Alzheimer’s disease 被引量:7
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作者 Lin Wang Bi-Qiang Zhou +5 位作者 Ying-Hong Li Qian-Qian Jiang Wei-Hong Cong Ke-Ji Chen Xiao-Min Wen Zheng-Zhi Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第1期226-232,共7页
Previous studies have shown that berberine has neuroprotective effects against Alzheimer’s disease,including antagonizing tau phosphorylation,and inhibiting acetylcholinesterase activity and neural cell apoptosis.How... Previous studies have shown that berberine has neuroprotective effects against Alzheimer’s disease,including antagonizing tau phosphorylation,and inhibiting acetylcholinesterase activity and neural cell apoptosis.However,its low bioavailability and adverse reactions with conventional administration limit its clinical application.In this study,we prepared berberine nanoliposomes using liposomes characterized by low toxicity,high entrapment efficiency,and biodegradability,and modified them with lactoferrin.Lactoferrin-modified berberine nanoliposomes had uniform particle size and high entrapment efficiency.We used the lactoferrin-modified berberine nanoliposomes to treat a mouse model of Alzheimer’s disease established by injection of amyloid-beta 1-42 into the lateral ventricle.Lactoferrin-modified berberine nanoliposomes inhibited acetylcholinesterase activity and apoptosis in the hippocampus,reduced tau over-phosphorylation in the cerebral cortex,and improved mouse behavior.These findings suggest that modification with lactoferrin can enhance the neuroprotective effects of berberine nanoliposomes in Alzheimer’s disease. 展开更多
关键词 ACETYLCHOLINEsTERAsE Alzheimer’s disease apoptosis BERBERINE brain targeting LACTOFERRIN NANOLIPOsOMEs neuroprotective effects Tau phosphorylation
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Surface-effects-dominated thermal and mechanical responses of zinc oxide nanobelts 被引量:6
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作者 A. J. Kulkarni. M. Zhou 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2006年第3期217-224,共8页
t Molecular dynamics (MD) simulations are carried out to characterize the mechanical and thermal responses of [011^-1]-oriented ZnO nanobelts with lateral dimensions of 21.22A × 18.95 A, 31.02A× 29.42 A, a... t Molecular dynamics (MD) simulations are carried out to characterize the mechanical and thermal responses of [011^-1]-oriented ZnO nanobelts with lateral dimensions of 21.22A × 18.95 A, 31.02A× 29.42 A, and40.81A ×39.89A over the temperature range of 300-1000 K. The Young's modulus and thermal conductivity of the nanobelts are evaluated. Significant surface effects on properties due to the highsurface-to-volume ratios of the nanobelts are observed. For the mechanical response, surface-stress-induced internal stress plays an important role. For the thermal response, surface scattering of phonons dominates. Calculations show that the Young's modulus is higher than the corresponding value for bulk ZnO and decreases by -33% as the lateral dimensions increase from 21.22 A × 18.95A to 40.81 A × 39.89A. The thermal conductivity is one order of magnitude lower than the corresponding value for bulk ZnO single crystal and decreases with wire size. Specifically, the conductivity of the 21.22 A × 18.95 A belt is approximately (31-18)% lower than that of the 40.81 A × 39.89 A belt over the temperature range analyzed. A significant dependence of properties on temperature is also observed, with the Young's modulus decreasing on average by 12% and the conductivity decreasing by 50% as temperature increases from 300 K to 1000 K. 展开更多
关键词 Zinc oxide nanobelts surface effects size dependence Young's modulus Thermal conductivity
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RELATIVE SEA LEVEL RISE AND ITS EFFECTS ON ENVIRONMENT AND RESOURCES IN CHINAS COASTAL AREAS 被引量:2
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作者 杨桂山 《Chinese Geographical Science》 SCIE CSCD 1995年第2期104-115,共12页
Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains of China will exceed 2-3 times over the golbal mean value during the first half part of the 21... Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains of China will exceed 2-3 times over the golbal mean value during the first half part of the 21st century. It will result in a series of adverse impacts on evolution of natural environment and socioeconomic development of the coastal area. This paper analyses environmental and resource effects induced by relative sea level rise in China's coastal areas on the basis of rough estimate of future relative sea level rise. These effects include inundating tidal flat and wetlands and increase in inundated risk of coastal habitable land,exacerbating storm surge. coastal erosion, flooding and salt water intrusion hazards.as well as endangering land. water. tourism and living resources and their utilization. 展开更多
关键词 China’s COAsTAL areas. RELATIVE sEA LEVEL RIsE environmental effect resource effect
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Study on the Overload and Dwell-Fatigue Property of Titanium Alloy in Manned Deep Submersible 被引量:2
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作者 WANG Ke WU Li +1 位作者 LI Yong-zheng SUN Xiao-peng 《China Ocean Engineering》 SCIE EI CSCD 2020年第5期738-745,共8页
With the rapid development of ocean technology, the deep-sea manned submersible is regarded as a high-tech equipment for the exploration and exploitation of ocean resources. The safety of manned cabin has a decisive e... With the rapid development of ocean technology, the deep-sea manned submersible is regarded as a high-tech equipment for the exploration and exploitation of ocean resources. The safety of manned cabin has a decisive effect on the whole system. Ti-6 Al-4 V with the superior strength-to-weight ratio and corrosion resistance has been used for the manned cabin. The manned cabin experiences loading spectrum with different maximum stresses and different dwell time during their service life. The load sequence effects on dwell fatigue crack growth behavior of Ti-6 Al-4 V under different dwell time are investigated experimentally in this paper. The experimental results show that the crack tip plastic zone is enlarged by the dwell time and the overload retardation zone increases with dwell time under the same overload rate. A dwell fatigue crack growth model is proposed by modifying the crack tip plastic zone under the loading history with combinations of the single overload and dwell time factors are included in the modified model. Based on the experimental data, the overload retardation zone and the crack growth rates of Ti-6 Al-4 V are predicted by the modified model. A reasonable model for the load sequence effect on the dwell fatigue crack growth rates of Ti-6 Al-4 V is verified. 展开更多
关键词 manned cabin dwell fatigue crack growth rate TI-6AL-4V load sequence effect
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Anti-Parkinsonian Therapy:Strategies for Crossing the Blood–Brain Barrier and Nano-Biological Effects of Nanomaterials 被引量:3
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作者 Guowang Cheng Yujing Liu +5 位作者 Rui Ma Guopan Cheng Yucheng Guan Xiaojia Chen Zhenfeng Wu Tongkai Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第6期350-398,共49页
Parkinson’s disease(PD),a neurodegenerative disease that shows a high incidence in older individuals,is becoming increasingly prevalent.Unfortunately,there is no clinical cure for PD,and novel anti-PD drugs are there... Parkinson’s disease(PD),a neurodegenerative disease that shows a high incidence in older individuals,is becoming increasingly prevalent.Unfortunately,there is no clinical cure for PD,and novel anti-PD drugs are therefore urgently required.However,the selective permeability of the blood–brain barrier(BBB)poses a huge challenge in the development of such drugs.Fortunately,through strategies based on the physiological characteristics of the BBB and other modifications,including enhancement of BBB permeability,nanotechnology can offer a solution to this problem and facilitate drug delivery across the BBB.Although nanomaterials are often used as carriers for PD treatment,their biological activity is ignored.Several studies in recent years have shown that nanomaterials can improve PD symptoms via their own nano-bio effects.In this review,we first summarize the physiological features of the BBB and then discuss the design of appropriate brain-targeted delivery nanoplatforms for PD treatment.Subsequently,we highlight the emerging strategies for crossing the BBB and the development of novel nanomaterials with anti-PD nano-biological effects.Finally,we discuss the current challenges in nanomaterial-based PD treatment and the future trends in this field.Our review emphasizes the clinical value of nanotechnology in PD treatment based on recent patents and could guide researchers working in this area in the future. 展开更多
关键词 Blood-brain barrier Parkinson’s disease Nasal delivery Biomimetic drug delivery Nano-biological effects
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Hydraulic model with roughness coefficient updating method based on Kalman filter for channel flood forecast 被引量:4
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作者 Hong-jun BAO Lin-na ZHAO 《Water Science and Engineering》 EI CAS 2011年第1期13-23,共11页
A real-time channel flood forecast model was developed to simulate channel flow in plain rivers based on the dynamic wave theory. Taking into consideration channel shape differences along the channel, a roughness upda... A real-time channel flood forecast model was developed to simulate channel flow in plain rivers based on the dynamic wave theory. Taking into consideration channel shape differences along the channel, a roughness updating technique was developed using the Kalman filter method to update Manning's roughness coefficient at each time step of the calculation processes. Channel shapes were simplified as rectangles, triangles, and parabolas, and the relationships between hydraulic radius and water depth were developed for plain rivers. Based on the relationship between the Froude number and the inertia terms of the momentum equation in the Saint-Venant equations, the relationship between Manning's roughness coefficient and water depth was obtained. Using the channel of the Huaihe River from Wangjiaba to Lutaizi stations as a case, to test the performance and rationality of the present flood routing model, the original hydraulic model was compared with the developed model. Results show that the stage hydrographs calculated by the developed flood routing model with the updated Manning's roughness coefficient have a good agreement with the observed stage hydrographs. This model performs better than the original hydraulic model. 展开更多
关键词 flood routing manning's roughness coefficient updating method Kalman filter Froude number saint-Venant equations hydraulic model
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Magnesium-L-threonate exhibited a neuroprotective effect against oxidative stress damage in HT22 cells and Alzheimer’s disease mouse model 被引量:3
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作者 Ying Xiong Yu-Ting Ruan +8 位作者 Jing Zhao Yu-Wen Yang Li-Ping Chen Ying-Ren Mai Qun Yu Zhi-Yu Cao Fei-Fei Liu Wang Liao Jun Liu 《World Journal of Psychiatry》 SCIE 2022年第3期410-424,共15页
BACKGROUND Oxidative stress results in the production of excess reactive oxygen species(ROS)and triggers hippocampal neuronal damage as well as occupies a key role in the pathological mechanisms of neurodegenerative d... BACKGROUND Oxidative stress results in the production of excess reactive oxygen species(ROS)and triggers hippocampal neuronal damage as well as occupies a key role in the pathological mechanisms of neurodegenerative disorders such as Alzheimer’s disease(AD).A recent study confirmed that magnesium had an inhibitory effect against oxidative stress-related malondialdehyde in vitro.However,whether Magnesium-L-threonate(MgT)is capable of suppressing oxidative stress damage in amyloidβ(Aβ)_(25-35)-treated HT22 cells and the AD mouse model still remains to be investigated.AIM To explore the neuroprotective effect of MgT against oxidative stress injury in vitro and in vivo,and investigate the mechanism.METHODS Aβ_(25-35)-induced HT22 cells were preconditioned with MgT for 12 h.APPswe/PS1dE9(APP/PS1)mice were orally administered with MgT daily for 3 mo.After MgT treatment,the viability of Aβ_(25-35)-treated HT22 cells was determined via conducting cell counting kit-8 test and the cognition of APP/PS1 mice was measured through the Morris Water Maze.Flow cytometry experiments were applied to assess the ROS levels of HT22 cells and measure the apoptosis rate of HT22 cells or hippocampal neurons.Expression of B-cell lymphoma 2(Bcl-2),Bcl-2-associated X(Bax),hypoxiainducible factor(HIF)-1α,NADPH oxidase(NOX)4,Aβ_(1-42) and phosphatidylinositol-3-kinase(PI3K)/protein kinase B(Akt)pathway proteins was quantified by Western blot.RESULTS In vitro data confirmed that Aβ_(25-35)-induced HT22 cells had a significantly lower cell viability,higher ROS level and higher apoptosis rates compared with those of control cells(all P<0.001).MgT prevented the Aβ_(25-35)-triggered oxidative stress damage by elevating viability and decreasing ROS formation and apoptosis of HT22 cells(all P<0.001).APP/PS1 mice exhibited worse cognitive performance and higher apoptosis rate of hippocampal neurons than wild-type(WT)mice(all P<0.01).Meanwhile,significant higher expression of Aβ_(1-42) and NOX4 proteins was detected in APP/PS1 mice than those of WT mice(both P<0.01).MgT also ameliorated the cognitive deficit,suppressed the apoptosis of hippocampal neuron and downregulated the expression of Aβ_(1-42) and NOX4 proteins in APP/PS1 mouse(all P<0.05).Moreover,MgT intervention significantly downregulated HIF-1αand Bax,upregulated Bcl-2 and activated the PI3K/Akt pathway both in vitro and in vivo(all P<0.05).CONCLUSION MgT exhibits neuroprotective effects against oxidative stress and hippocampal neuronal apoptosis in Aβ_(25-35)-treated HT22 cells and APP/PS1 mice. 展开更多
关键词 Alzheimer’s disease MAGNEsIUM Neuroprotective effect Oxidative stress HIPPOCAMPAL Neuronal apoptosis
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A novel binary effective medium model to describe the prepeak stressstrain relationship of combined bodies of rock-like material and rock 被引量:2
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作者 Tienan Wang Yue Zhai +2 位作者 Huan Gao Yubai Li Ruifeng Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第5期601-616,共16页
Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body ... Combined bodies of rock-like material and rock are widely encountered in geotechnical engineering,such as tunnels and mines.The existing theoretical models describing the stress-strain relationship of a combined body lack a binary feature.Based on effective medium theory,this paper presents the governing equation of the“elastic modulus”for combined and single bodies under triaxial compressive tests.A binary effective medium model is then established.Based on the compressive experiment of concretegranite combined bodies,the feasibility of determining the stress threshold based on crack axial strain is discussed,and the model is verified.The model is further extended to coal-rock combined bodies of more diverse types,and the variation laws of the compressive mechanical parameters are then discussed.The results show that the fitting accuracy of the model with the experimental curves of the concretegranite combined bodies and various types of coal-rock combined bodies are over 95%.The crack axial strain method can replace the crack volumetric strain method,which clarifies the physical meanings of the model parameters.The variation laws of matrix parameters and crack parameters are discussed in depth and are expected to be more widely used in geotechnical engineering. 展开更多
关键词 Combined body stress-strain relationship Hooke’s law effective medium theory stress threshold determination
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