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背离伦理的科学技术会给我们带来什么?

自然辩证法通讯 2005年第2期27卷 20-22页

作者：童恒萍王会波华南师范大学政治与行政学院广东广州510631

一、'没有伦理学的科学是盲目的,而没有科学的伦理学是空洞的.'[1]科学技术对于当今人类社会是物质文明建设的决定性因素,同时,由于其背后所蕴含的世界观、价值论、方法论准则和伦理学规范,它在精神文明的建设中也起着至关重要的作用.

关键词：科学技术伦理学价值观生态伦理

Insight into the particle shape on the impact of dry granular flow against a rigid barrier: A DEM study

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Journal of Earth Science 2025年

作者： Rui-Xiao Zhan dong Su Xiang-Sheng Chen Yuan-Jun Jiang Guo-ping Lei Jing-Jing Yu Key Laboratory for Resilient Infrastructures of Coastal Cities (MOE)， Shenzhen University College of Civil and Transportation Engineering， Shenzhen University School of Architecture and Urban Planning， Shenzhen University Shenzhen Key Laboratory of Green， Efficient and Intelligent Construction of Underground Metro Station， Shenzhen University Institute of Mountain Hazards and Environment， Chinese Academy of Sciences School of Transportation， Civil Engineering & Architecture， Foshan University

The effect of particle shape on the impact of dry granular flow remains an open area for further investigation. Five distinct particle shapes were examined in this study using discrete element simulations after calibrating the numerical model using a published work. The findings indicated that the particle shape had a significant influence on granular mobility. With negligible variations in normalized kinetic energy between particles of different shapes， the effect of particle shape on the increasing rate of kinetic energy became more obvious. All irregular particle scenarios had longer accumulated particle lengths down the channel than spherical particles. Variations in particle shape led to adjustments in the distribution of impact forces on the barrier. These findings substantially enhance our understanding of the distinctive effects of particle shapes on the impact mechanism of dry granular flow.

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基于Si-rich SiNx/N-rich SiNy多层膜结构电致发光特性研究

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物理学报 2009年第3期58卷 2072-2076页

作者：黄锐董恒平王旦清陈坤基丁宏林徐骏李伟马忠元南京大学物理系固体微结构物理国家重点实验室南京210093 韩山师范学院物理与电子工程系潮州521041

利用等离子体增强化学气相沉积法制备了富硅氮化硅/富氮氮化硅多层膜,并以此氮化硅基多层膜作为有源层构建电致发光器件,在室温下观察到了较强的电致可见发光.在此基础上,研究多层膜结构中作为势垒层的富氮氮化硅层对器件电致发光性质... 详细信息

利用等离子体增强化学气相沉积法制备了富硅氮化硅/富氮氮化硅多层膜,并以此氮化硅基多层膜作为有源层构建电致发光器件,在室温下观察到了较强的电致可见发光.在此基础上,研究多层膜结构中作为势垒层的富氮氮化硅层对器件电致发光性质的影响,实验结果表明通过改变势垒层的Si/N组分,调制其势垒高度,器件的电致发光效率可得到显著地提高.

关键词：电致发光多层膜氮化硅

Limit equilibrium method(LEM) of slope stability and calculation of comprehensive factor of safety with double strength-reduction technique

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Journal of Mountain Science 2017年第11期14卷 2311-2324页

作者： DENG dong-ping LI Liang ZHAO Lian-heng School of Civil Engineering Central South University

When the slope is in critical limit equilibrium(LE) state, the strength parameters have different contribution to each other on maintaining slope stability. That is to say that the strength parameters are not simultaneously reduced. Hence, the LE stress method is established to analyze the slope stability by employing the double strengthreduction(DSR) technique in this work. For calculation model of slope stability under the DSR technique, the general nonlinear Mohr–Coulomb(M–C) criterion is used to describe the shear failure of slope. Meanwhile, the average and polar diameter methods via the DSR technique are both adopted to calculate the comprehensive factor of safety(FOS) of slope. To extend the application of the polar diameter method, the original method is improved in the proposed method. After comparison and analysis on some slope examples, the proposed method's feasibility is verified. Thereafter, the stability charts of slope suitable for engineering application are drawn. Moreover, the studies show that:(1) the average method yields similar results as that of the polardiameter method;(2) compared with the traditional uniform strength-reduction(USR) technique, the slope stability obtained using the DSR techniquetends to be more unsafe; and(3) for a slope in the critical LE state, the strength parameter φ, i.e., internal friction angle, has greater contribution on the slope stability than the strength parameters c, i.e., cohesion.

关键词： Slope stability Nonlinear Mohr-Coulomb (M-C) criterion Double strength-reduction(DSR) technique Slope Comprehensive Factor ofSafety (FOS) Stability charts

Limit equilibrium stability analysis of slopes under external loads

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Journal of Central South University 2016年第9期23卷 2382-2396页

作者： DENG dong-ping ZHAO Lian-heng LI Liang School of Civil Engineering Central South University Changsha 410075 China

Two calculation modes for the effect of external load on slope stability, i.e., mode I in which the external load is thought to act on slope surface, and mode II in which the external load is thought to act on slip surface along the force action line, were considered. Meanwhile, four basic distribution patterns of external load were used, of which complex external loads could be composed. In analysis process, several limit equilibrium methods, such as Swedish method, simplified Bishop method, simplified Janbu method, Spencer method, Morgenstern-Price(M-P) method, Sarma method, and unbalanced thrust method, were also adopted to contrast their differences in slope stability under the external load. According to parametric analysis, some conclusions can be obtained as follows:(1) The external load, with the large magnitude, small inclination angle, and acting position close to the slope toe,has more positive effect on slope stability;(2) The results calculated using modes I and II of external load are similar, indicating that the calculation mode of external load has little influence on slope stability;(3) If different patterns of external loads are equivalent to each other, their slope stability under these external loads are the same, and if not, the external load leads to the better slope stability,as action position of the resultant force for external load is closer to the lower sliding point of slip surface.

关键词： slope stability calculation mode of external load distribution pattern of external load limit equilibrium slip surface factor of safety (FOS)

Limit equilibrium analysis for stability of soil nailed slope and optimum design of soil nailing parameters

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Journal of Central South University 2017年第11期24卷 2496-2503页

作者： DENG dong-ping LI Liang ZHAO Lian-heng School of Civil Engineering Central South UniversityChangsha 410075China

Reinforcement of slopes using soil nailing can effectively improve slope stability, and it has been widely used in upgrading cut slopes. Based on the assumptions of stresses on the slip surface, a new method for analyzing the stability of a slope reinforced with soil nails was established in the limit equilibrium theory framework, by considering that slope sliding occurs owing to shear failure of the slip surface, which subjects to Mohr–Coulomb(M–C) strength criterion. Meanwhile, in order to easily analyze the stability of a soil nailed slope in actual engineering and facilitate optimum design of parameters for soil nailing, factor of safety(FOS) contour curve charts were drawn on the basis of the established linear proportional relationship between the spacing of soil nails and slope height, and the length of soil nails and slope height. Then, by analyzing and verifying the results obtained from classic examples, some conclusions can be got as follows: 1) The results obtained from the current method are close to those obtained from the traditional limit equilibrium methods, and the current method can provide a strict solution for the slope FOS as it satisfies all the static equilibrium conditions of a sliding body, thus confirming the feasibility of the current method; 2) The slope FOS contour curve charts can be used not only to reliably analyze the stability of a soil nailed slope, but also to design optimally the parameters of soil nailing for the slope with a certain safety requirement.

关键词： slope stability soil nailing limit equilibrium factor of safety contour curve optimum design

Metastable seed-crystals: epitaxial growth of branched-array organic heterostructure nanowires

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Science China Chemistry 2025年

作者： Jin Feng Zhen-Yu Geng Ting-Yao Song Ying-Xin Ma Chuan-Zeng Wang Wei Zhang Hong-Tao Lin Jin Zhou Shu-ping Zhuo Shu-Hai Chen Xue-dong Wang School of Chemistry and Chemical Engineering Shandong University of Technology Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & DevicesSoochow University College of Chemistry and Chemical Engineering Hunan Normal University

Tunable light–matter interactions are exhibited by organic low-dimensional crystals, making these crystals a promising platform for organic photonics. However, the precise synthesis of organic low-dimensional crystals remains challenging due to the stochastic nature of molecular nucleation processes. Herein, the directed nucleation process is driven by the introduction of metastable seed-crystals as the trunk, which ultimately leads to branched-array organic heterostructures. The successful formation of organic heterostructures with high-density branched arrays is attributed to the highest attachment energy (Eatt（023）=-104.25 kcal mol-1) of the exposed （023） crystal plane during the seed-crystal growth route. Significantly, these as-prepared heterostructures inherently have an ultralow lattice mismatch ratio η of 0.7%between trunk and branch, which contributes to the multi-channel photon transportation. Therefore, this work provides valuable insights into a versatile synthetic strategy for accessing low-dimensional heterostructures for integrated optoelectronics.

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More Requests, Less Cost： Uncertain Inter-Datacenter Traffic Transmission with Multi-Tier Pricing

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Journal of Computer Science & Technology 2018年第6期33卷 1152-1163页

作者： Xiao-dong dong Sheng Chen Lai-ping Zhao Xiao-Bo Zhou heng Qi Ke-Qiu Li Tianjin Key Laboratory of Advanced Networking College of Intelligence and Computing Tianjin University Tianjin 300350 China School of Computer Science and Technology Dalian University of Technology Dalian 116024 China

With the multi-tier pricing scheme provided by most of the cloud service providers （CSPs）, the cloud userstypically select a high enough transmission service level to ensure the quality of service （QoS）, due to the severe penalty ofmissing the transmission deadline. This leads to the so-called over-provisioning problem, which increases the transmissioncost of the cloud user. Given the fact that cloud users may not be aware of their traffic demand before accessing the network,the over-provisioning problem becomes more serious. In this paper, we investigate how to reduce the transmission cost fromthe perspective of cloud users, especially when they are not aware of their traffic demand before the transmission *** key idea is to split a long-term transmission request into several short ones. By selecting the most suitable transmissionservice level for each short-term request, a cost-efiqcient inter-datacenter transmission service level selection framework isobtained. We further formulate the transmission service level selection problem as a linear programming problem andresolve it in an on-line style with Lyapunov optimization. We evaluate the proposed approach with real traffic data. Theexperimental results show that our method can reduce the transmission cost by up to 65.04%.

关键词： traffic uncertainty inter-datacenter transmission multi-tier pricing scheme

Endocrine Disruption of Cadmium in Rats Using the OECD Enhanced TG 407 Test System

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Biomedical and Environmental Sciences 2014年第12期27卷 950-959页

作者： WANG heng Juan LIU Zhao ping JIA Xu dong CHEN Hao TAN Yan Jun Key Laboratory of China National Center for Food Safety Risk Assessment NHFPC

Objective To evaluate the endocrine disrupting effects of cadmium （Cd） using OECD enhanced TG407 test guideline. Methods Sprague-Dawley （SD） rats were randomly divided into six groups and accordingly administered with 0, 1, 2.5, 5, 10, 20 mg/***/day of Cd by gavage for 28 days. Body weight, food consumption, hematology, biochemistry, sex hormone levels, urinary β2-microglobulin, organ weights and histopathology and estrous cycle were detected. Results Cd could significantly decrease animals＇ body weight （P〈0.05）. Serum luteinizing hormone （LH） at 10-20 mg/*** groups and testosterone （T） at 2.5 and 10 mg/*** groups decreased significantly （P〈0.05）. However, no statistically significant change was found in urinary β2-microglobulin among Cd-treatment groups （P〉0.05）. Endpoints related to female reproduction including uterus weight and histopathological change at 10-20 mg/*** groups showed significant increase （P〈0.05）. While among male rats in 2.5, 10, 20 mg/*** groups, weight of prostate, thyroids, and seminal vesicle glands significantly decreased （P〈0.05）. Moreover, no histopathological change was observed in kidney. Conclusion Results suggested that Cd can cause endocrine disrupting effects in SD rats. Comparing with possible renal toxicity of Cd, its toxicity on endocrine system was more sensitive.

关键词： OECD Enhanced Test Guideline 407 Endocrine Disrupting Cadmium Renal toxicity