Ab Initio Study of the Dynamical Si-O Bond Breaking Event in α-Quartz

The Si-O bond breaking event in the a-quartz at the first triplet （T1） excitation state is studied by using ab initio molecular dynamics （AIMD） and nudged elastic band calculations. A meta-stable non-bridging oxygen hole center and E1 center （NBOHC-E） is observed in the AIMD which consists of a broken Si-O bond with a Si-O distance of 2.54A. By disallowing the re-bonding of the Si and 0 atoms, another defect configuration （lll- Si/V-Si） is obtained and validated to be stable at both ground and excitation states. The NBOHC-E is found to present on the minimal energy pathway of the initial to IlI-Si/V-Si transition, showing that the generating of the NBOHC-E is an important step of the excitation induced structure defect. The energy barriers to produce the NBQHC-E＇ and Ⅲ-Si/V-Si defects are calculated to be 1.19 and 1.28eV, respectively. The electronic structures of the two defects are calculated by the self-consistent GW calculations and the results show a clear electron transition from the bonding orbital to the non-bonding orbital.

A^1HNMR STUDY ON THE FORMATION AND BREAKING OF INTRAMOLECULAR HYDROGEN BONDS OF BILIRUBIN IN CDCl_3-DMSO-d_6 BINARY SOLVENT

The formation and breaking of intramolecular hydrogen bonds of bilirubin in CDCl_3-DMSO-d_6 binary solvent have been investigated by means of NMR spectroscopy.The chemical shifts of protons at dipyrrinone lactam C=O and N-H,Pyrrole N-H,C-5,C-15 and methylene groups of 8,12-propionic acid side-chains changed markedly as a function of composition of the binary solvent.The hydrogen bond formation is dependent on the conformation of propionic acid side-chains.

A Comparative Study of Numerical Models for Wave Propagation and Setup on Steep Coral Reefs

Complex factors including steep slopes, intense wave breaking, large bottom friction and remarkable wave setup should be considered while studying wave propagation over coral reefs, and how to simulate wave propagation and setup on coral reefs efficiently has become a primary focus. Several wave models can be used on coral reefs as have been published, but further testing and comparison of the reliability and applicability of these models are needed. A comparative study of four numerical wave models (i.e., FUNWAVE-TVD, Coulwave, NHWAVE and ZZL18) is carried out in this paper. These models’ governing equations and numerical methods are compared and analyzed firstly to obtain their differences and connections;then the simulation effects of the four wave models are tested in four representative laboratory experiments. The results show that all four models can reasonably predict the spectrum transformation. Coulwave, NHWAVE and ZZL18 can predict the wave height variation more accurately;Coulwave and FUNWAVE-TVD tend to underestimate wave setup on the reef top induced by spilling breaker, while NHWAVE and ZZL18 can predict wave setup relatively accurately for all types of breakers;NHWAVE and ZZL18 can predict wave reflection by steep reef slope more accurately. This study can provide evidence for choosing suitable models for practical engineering or establishing new models.

WRITING ENGLISH THE ENGLISH WAY——A STUDY OF THE CAUSES OF CHINGLISH

The linguistic interference of one’s mother tonguealways poses an obstacle to his or her learning of for-eign languages and teachers should try their best to dis-cover means to overcome this.This paper analyzes theforms and causes of Chinglish,which is created byadult Chinese learners of English through their moth-er-tongue interference.After a contrastive study ofsome linguistic features between Chinese and English,the author lists ten common forms of Chinglish,il-lustrated with examples from his own teaching prac-tice,and points out their respective causes and somepossible measures to eradicate them.

Click Your Way to Study Opportunities in China

Do you believe that with just a click of your mouse you can complete an application to study in China? The China University and College Admission System (known as CHIWEST) can help you make it happen. According to the Ministry of Education, in 2008,

宋代民众的诉讼与官府的审理——读《名公书判清明集》的几点认识

“好讼”是宋代比较普遍的民情,这一现象在《名公书判清明集》中有具体印证。凭借大量的案例,再联系历史实情,可知“好讼”源于官吏贪腐、豪强奸恶,也是民众学法懂法、有文明维权意识的表现。江西农耕经济旺盛,耕地紧俏,因而争夺田产所有权的讼案很多。审理纠纷时因官员品德才干差异,有的贪财,甚至“自紊其法”,遂判决不公正。诸多关于教化与刑罚并举的判词,启发我们加深对《白鹿洞书院揭示》的理解,朱熹强调圣贤教人之道,也告诫生徒若不听教育,必将实施“学规”,予以惩罚。《名公书判清明集》是研究断代史、社会史、法制史等的珍贵资料,至今不失其借鉴警示意义。

聚酯缆动力学行为计算方法研究

The dynamic stiffness of polyester rope presents a complex mechanical performance,and the search for an appropriate calculation method to simulate this property is important.Distorted simulation results eventually yield inaccurate line tension and vessel offset predictions,with the inaccuracy of vessel offset being particularly large.This paper proposes a flexible calculation method for the dynamic behavior of polyester rope based on the dynamic stiffness model.A real-time varying stiffness model of polyester rope is employed to simulate tension response through rope strain monitoring.Consequently,a simulation program is developed,and related case studies are conducted to explore the differences between the proposed method and analytical procedure of the DNV standard.Orcaflex is used to simulate the results of the latter procedure for comparison.Results show the convenience and straightforwardness of the procedure in the selection of an approximate dynamic stiffness model for polyester rope,which leads to an engineering-oriented approach.However,the proposed method is related to line property,which can directly reflect the dynamic behavior of polyester rope.Thus,a flexible calculation method may provide a reference for the simulation of the dynamic response of polyester mooring systems.

Study of Bouble－strand Breaks in Fish Sperm DNA Molecules after Heavy－ion Irradiation by Pulsed－field Gel Electrophoresis

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汽车式多功能破障车车架的有限元分析与实验研究

车架是多功能破障车非常重要的受力构件,其结构性能直接关系到整车的安全问题。建立破障车车架有限元模型,四点支撑和推土工况的静强度分析,完成样车车架应力测试试验。分析结果表明四点支撑和推土工况车架强度不足。试验结果表明各工况测点数据与有限元计算值相差较小,四点支撑工况测点1区域发生了塑性变形,推土工况测点1和测点12发生了塑性变形,验证了车架有限元分析的正确性。对车架进行优化设计,提供了三种车架改进方案,方案二为最佳方案,改进方案的车架满足工作要求,为相关车辆车架的分析研究提供了技术方法。

Modeling of Fixed Bed Adsorption Column Parameters of Iron(II) Removal Using Ferrihydrite Coated Brick

Fixed-bed operating experimental column conditions were studied to evaluate the performance of brick from Bangui Region (in Central African Republic), coated with iron oxyhydroxide (ferrihydrite) for the removal of iron(II) from aqueous solution. The prediction of theoretical breakthrough profiles using Bohart and Adams sorption model was employed to achieve characteristic parameters such as depth of exchange zone, time required for exchange zone to move vertically, moving rate for the exchange zone and adsorption capacity useful for fixed-bed column reactor was investigated under varying operating conditions. The effects of bed depth and flow rate on iron(II) adsorption were studied. Our finding revealed that the Brick from Bangui Region (in Central African Republic), coated with ferrihydrite was a very efficient media for the removal of Fe(II) ions from water. The experimental data showed that the depth and the moving rate (10.3 ± 0.6 cm) and (0.208 ± 0.006 cm/min) respectively of the exchange zone (adsorption zone) were independent of variability of the height of the adsorbent bed column, however the variations of the flow rate affect the moving rate of the exchange zone. The bed depth service time (BDST) model was used and permitted us to predict the service times of columns operated at various flow rates and bed depths and these predicted values were compared with the experimental values.

滑坡涌浪在渐溃水库中传播过程试验研究

通过模型试验的方法,对滑坡涌浪在渐溃水库中的传播过程进行重演。研究表明,溃坝过程导致的库区水深下降对涌浪的波高、波长和周期均有很大影响;溃坝和非溃坝条件下,涌浪高度随时间衰减趋势都是相似的;相比非溃坝情况,渐溃条件下涌浪传播到坝体时波高衰减幅度更少。

溃坝模型试验研究综述

从溃坝洪水、溃坝机理等方面对溃坝模型试验研究情况进行了详细回顾,概括总结了国内外在溃坝模型试验方面所取得的主要成果,并从研究内容、相似理论、模型比尺及测试手段等方面对溃坝模型试验的现有水平及未来发展动向进行了分析,认为今后仍需大力开展溃坝模型试验研究,并以溃坝机理研究为重点,不断提高试验研究水平,为大坝安全提供有力的技术保障。

折点氯化法处理高NH_3-N含钴废水试验与工程实践

高NH3-N化学冶金废水是一种难处理废水。针对该类废水NH3-N高,含盐量高,难以生化处理的特征,首先对应用折点氯化法处理该类废水进行了实验室小试研究,根据试验结果进行了工程实践,出水达到了国家二级标准要求,并对工程实践中需注意的问题进行了总结。

心理咨询师突破保密的态度和决策

目的:了解在心理咨询中,咨询师对突破保密的伦理原则的态度以及咨询师在不同情境下保密突破的决策。方法:对100名心理咨询师,采用自编"心理咨询师突破保密的态度和决策问卷",考察可能影响心理咨询师对待保密原则的态度和决策的因素。结果:"来访者有高伤害他人风险"、"来访者有高受伤害风险"时,从业时间短的咨询师(5年以下)突破保密态度得分高于从业时间长的咨询师(5年以上)[(1.2±0.8)vs.(1.1±0.3),(1.4±1.0)vs.(1.2±0.5);均P<0.05];"来访者有高受伤害风险"时,接受督导的咨询师突破保密态度得分低于未接受督导的咨询师[(1.2±0.6)vs.(2.0±1.7);P<0.01],而"未成年来访者家长要求了解咨询细节"时,接受督导咨询师突破保密态度得分高于未接受督导咨询师[(5.3±1.8)vs.(4.2±2.1),P=0.052];咨询师在来访者主动计划犯罪时突破保密的决策得分低于来访者知道犯罪计划时的得分[(1.7±1.2)vs.(2.8±2.0),P<0.01];当法庭要求报告相关情况时,咨询师在来访者因家暴犯罪接受调查时突破保密的决策得分低于来访者因无关犯罪接受调查时的得分[(2.0±1.6)vs.(3.5±2.2),P<0.01]。结论:咨询师的保密态度与决策在一定程度上会受到其从业时间、是否接受督导及来访者具体情境的影响。

不同厚度岩层破断模式实验研究

顶板破断是采场矿压显现的根本原因,现有很多成果是基于梁或薄板模型而来,而顶板的厚度直接影响了顶板的破断行为。自主研制了采空区顶板破断模拟实验装置,在均布载荷作用下对四边固支不同厚度顶板进行了破坏实验研究。实验结果验证了薄板基本以沿长边的"O-X"型断裂模式为主,而厚板不仅有沿长边的"O-X"型和沿短边的"O-X"型断裂模式,还有"O-?"型的断裂方式。研究结果表明:薄板破断主要受到最大弯曲应力的影响。随着板厚度增加,横向剪切力的作用在加强,此时厚板的破坏主要受到弯曲和剪切耦合作用,导致其破坏行为更为复杂。

PDC切削齿破岩受力的试验研究

试验模拟了切削面积、接触弧长、切削面形状、切削齿后倾角和岩石性能对PDC切削齿破岩受力的影响。结果表明,采用接触弧长、切削面积和岩石可钻性表征切削面的几何形状和岩石性能与PDC切削齿破岩的实质相符。PDC切削齿单位切削面积上的切向力和正压力随着接触弧长、切削面积、切削齿后倾角和岩石可钻性级值的增大而增大,并与切削面积与接触弧长的乘积呈显著的线性关系。当后倾角小于10°时,切削齿受力较小。根据试验结果,建立了PDC切削齿破岩的受力模型。

多孔射流钻头破岩钻孔规律试验研究

利用自行研制的射流破岩系统,对淹没和围压条件下多孔射流钻头的破岩钻孔规律进行了试验研究,重点考虑了水力参数(冲蚀时间、射流压力、围压、喷距)和结构参数(孔眼数量和侧向孔眼扩散角)对破岩效果的影响,结果表明:随着冲蚀时间的增加,破岩效果先增加,后趋于平缓;随着射流压力的增大破岩效果随之增大;随着围压的增加破岩效果随之减小;随着喷距的增加破岩效果呈先增大后减小的趋势,存在最优喷距范围;随着孔眼数量的增多,破岩成孔形状越来越圆整;随着侧向孔眼扩散角的增大,破岩效果呈先增大后减小趋势,存在最优扩散角范围。试验结果可为多孔射流钻头水力参数选择和结构参数设计提供依据。

双射流破岩钻孔参数实验研究

双射流是由由心直射流和同轴的环形旋转射流形成的一种新型高效射流，用双射流能够克服门限压力与高破岩比能的制约而高效破岩。采用破岩实验研究了喷嘴锥角、叶片出口角、内喷嘴直径、喷距和压力5个主摹参数对双射流破岩效果的影响。结果表明，喷嘴入口锥角为60°、叶片出口角为18°的喷嘴产生的射流具有较强的破岩能力；当双射流喷嘴当量直径一定时，大的内喷嘴直径获得的破岩深度较大但会减小破岩体积；实验条件下，双射流破岩的最优喷距为10～20m，破岩门限压力为20～25MPa，破岩体积随压力的增加而增加。