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烷基铝浓度对丙烯高温聚合动力学行为的影响

高分子材料科学与工程 2006年第1期22卷 40-43页

作者：高明智 Peter J t t.it 丁春敏中国石化北京化工研究院北京100013 Department of Chemistry UM iSt Manchester M601QD UK.

研究了在70℃和93℃烷基铝浓度对M gC l2/DNBP/t.iC l4-A lE t3/DCPDM S催化体系催化丙烯聚合动力学行为的影响,结果显示,高温下烷基铝浓度的提高更加速了催化剂活性的衰减及催化剂活性中心稳定性的降低。随着聚合反应的进行,单体在固... 详细信息

研究了在70℃和93℃烷基铝浓度对M gC l2/DNBP/t.iC l4-A lE t3/DCPDM S催化体系催化丙烯聚合动力学行为的影响,结果显示,高温下烷基铝浓度的提高更加速了催化剂活性的衰减及催化剂活性中心稳定性的降低。随着聚合反应的进行,单体在固体催化剂表面的吸附常数KM将降低,但烷基铝在固体催化剂表面的吸附常数KA的变化在不同聚合温度下是不同的,70℃时,烷基铝在固体催化剂表面的吸附常数KA增大,而93℃,当S i/t.i比恒定时,KA基本不变,当A l/S i比恒定时,KA增大。

关键词：丙烯聚合 Ziegler-Natta催化剂动力学行为稳定指数吸附常数

A tabletop, ultrashort pulse photoneutron source driven by electrons from laser wakefield acceleration

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Matter and Radiation at Extremes 2017年第6期2卷 296-302页

作者： X.J.Jiao J.M.Shaw t.Wang X.M.Wang H.tsai P.Poth i.Pomerantz L.A.Labun t.toncian M.C.Downer B.M.Hegelich Center for High Energy Density Science University of TexasAustinTX 78712USA institut fur Kernphysik Technische Universitat DarmstadtGermany the School of Physics and Astronomy Tel-Aviv UniversityTel-Aviv69978Israel

Relativistic electron beams driven by laser wakefield acceleration were utilized to produce ultrashort neutron *** experiment was carried out on the 38 fs,~0.5 J,800 nm ti:Sapphire laser in the 10 tW Ut 3 laser lab at University of texas at *** target gas was a high density pulsed gas jet composed of 90%He and 10%N *** laser pulse with a peak intensity of 1.5×10^(18) W/cm^(2) interacted with the target to create a cylindrical plasma channel of 60 mm radius(FWHM)and 1.5 mm length(FWHM).Electron beams of~80 pC with the Gaussian energy dist.ibution centered at 37 MeV and a width of 30 MeV(FWHM)were produced via laser wakefield *** fluences of~2.4×10^(6) per shot with hundreds of ps temporal length were generated through bremsstrahlung and subsequent photoneutron reactions in a 26.6 mm t.ick tungsten *** were compared with those of simulations using EPOCH and GEANt4,showing agreement.in electron spectrum,neutron fluence,neutron angular dist.ibution and conversion rate.

关键词： Neutron source LWFA Photoneutron reaction

Magnesium alloys as extremely promising alternatives for temporary orthopedic implants-A review

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Journal of Magnesium and Alloys 2023年第8期11卷 2688-2718页

作者： C.A.Niranjan t.Raghavendra Madhuri P.Rao C.Siddaraju M.Gupta Vikram Kumar S.Jain R.Aishwarya Department of indust.ial Engineering and Management Ramaiah Institute of TechnologyBengaluru-54India Department of Mechanical Engineering National Institute of EngineeringMysuru-08India Department of Chemistry B.M.S.College of EngineeringBengaluru-19India Department of Mechanical Engineering Ramaiah Institute of TechnologyBengaluru-54India Department of Mechanical Engineering NUS Singapore-75Singapore Department of Metallurgical and Materials Engineering Indian Institute of TechnologyMadras-36India

Mg alloys are emerging as potential and very promising alternatives for replacing permanent metallic implant materials such as steels and titanium in applications where the implants need to be removed following healing through revision *** of Mg alloys for implant application is seen as a game changer and Mg alloys are almost perfect materials for the future in both engineering and biomedical *** review therefore focuses on highlighting significance of Mg alloys in biomedical field and risks of using permanent metallic implants particularly when the implants are no longer required after the injury is *** t.is review,importance of orthopedic implants in present scenario,serious concern related to accidents that are causing permanent disabilities,demand in orthopedic implant market worldwide,potential applications of Mg based materials and their compatibility in biological environment.is presented and *** addition,degradation rate,major reactions associated with Mg based materials and effect of alloying elements on implant performance are also discussed based on in-vivo *** advances in development of Mg alloys through various techniques and their performance in in-vitro conditions are also *** ways to eliminate the limitations of Mg alloys include alloying,melt purification,surface alterations,surface modifications,chemical treatment,secondary processing *** *** and opportunities for Mg alloys to become ideal implant material is also addressed.

关键词： Accidents Fractures Burden of fracture Magnesium Ultimate alternative Degradation rate Alloying Melt purification Coating

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小神探怪案子

少年大世界（小学4－6年级） 2018年第3期 14-17页

作者：王t.--i

第九集五色房间魔术师朱亚马克在神探学院的名声越来越大．许多小侦探迷们都崇拜这个帅气聪明的侦探小子。马克并没有骄傲，米琪儿也为表哥感到开心和自豪。不过随之而来的是，马克遇到了许多挑战者。今天．就有一位神秘的魔术师朱亚... 详细信息

第九集五色房间魔术师朱亚马克在神探学院的名声越来越大．许多小侦探迷们都崇拜这个帅气聪明的侦探小子。马克并没有骄傲，米琪儿也为表哥感到开心和自豪。不过随之而来的是，马克遇到了许多挑战者。今天．就有一位神秘的魔术师朱亚想要挑战马克。

关键词：魔术师马克挑战者侦探

Gabapentin prevalence:clinical and forensic experience in ***,Missouri,USA

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Forensic Sciences Research 2021年第4期6卷 218-223页

作者： Sarah B.Riley Kelsie Garbutt Chelsea Crow t.Scott.isbell Anthony J.Scalzo school of Medicine Department of Pathology saint Louis Universityst.LouisMissouriUs school of Medicine Department of Pediat.ics saint Louis Universityst.LouisMissouriUs Department of sociology and anthropology Forensic sciences Programsaint Louis Universityst.LouisMissouriUSA

Gabapentin(Neurontin)is an anti-epileptic drug that has had wide off-label prescription use since market release due to presumed negligible abuse ***,trends in drug misuse have demonstrated that gabapentin misuse is occurring,particularly in those with a history of opioid *** is concerning,because although gabapentin has no direct ligand activity at opioid receptors,it does potentiate the analgesic effect of opioids,and concurrent use of gabapentin and opioids may increase the risk of respiratory depressive effects of *** study investigates the incidence of gabapentin detected in urine samples collected for clinical drug screening purposes in a local hospital emergency department and in postmortem samples submitted by medical examiners in the *** metropolitan *** prevalence of gabapentin and co-detected drugs in both populations is contrasted,compared,and *** study found that 30%of urine samples collected from patients with suspected drug intoxication presenting to SSM Health Saint Louis University Hospital,a quaternary care medical center,were positive for gabapentin,and nearly two t.irds of those were also positive for *** a 6-month period,the incidence of gabapentin positive postmortem cases increased from 18%to 20%.Nearly all gabapentin positive postmortem cases were also positive for an opioid,the most significant being fentanyl,suggesting that gabapentin misuse may be due to its potentiating effect of opioid drug *** study also highlights the limited utility of immunoassay-based urine drug screens.

关键词： Forensic toxicology clinical toxicology substance misuse gabapentin urine drug screening postmortem mass spectrometry

氰化物污染土壤修复工程环境足迹评估方法和案例研究

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中国环境科学 2024年第5期44卷 2905-2915页

作者：桑春晖杨欣桐张红振肖萌刘瑞平孟藤藤李香兰北京师范大学地理科学学部全球变化与地球系统科学研究院北京100875 生态环境部环境规划院土壤保护与景观设计中心北京100012 山东大成环境修复有限公司山东淄博255099

在界定评估边界、细化数据清单和系统构建评估流程方法的基础上,采用国际上广泛应用的环境足迹分析计算工具Spreadsheets for Environmental Footprint Analysis(SEFA),以山东某氰化物污染地块为例,基于实际获取数据,进行环境足迹的定... 详细信息

在界定评估边界、细化数据清单和系统构建评估流程方法的基础上,采用国际上广泛应用的环境足迹分析计算工具Spreadsheets for Environmental Footprint Analysis(SEFA),以山东某氰化物污染地块为例,基于实际获取数据,进行环境足迹的定量评价.结果表明,修复工程污染土方量74948m^(3),材料消耗量2249t,固废产生量4.19t,水资源消耗量2714m^(3),废水产生量2481m^(3),能源消耗量4274万MJ,温室气体(GHG)排放量为2463t CO_(2)-eq.原位化学氧化相对原地异位化学氧化的环境影响更小,去除每千克氰化物的能源效率和GHG排放强度分别为6415MJ/kg和339.11kg CO_(2)-eq/kg,约占异位化学氧化的25%.案例结果表明,SEFA能够快速、高效地定量评估氰化物污染修复工程的环境影响,上游原材料的使用导致的间接排放是环境足迹的主要来源,设备使用时长和材料用量是影响评估结果的关键参数.

关键词：原位化学氧化异位化学氧化过硫酸钠绿色可持续修复碳排放

Study on Liquefying Simulation test of Ret.ining Structure Ground of Kobe Port

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Journal of Earth Science 1998年第2期17卷 82-84页

作者： Fang Yun Faculty of Environmental Science and Geotechnique, China University of Geosciences, Wuhan 430074 Ghalandarzadeh A. towhata i. Orita t. Department of Civil Engineering, University of tokyo, Japan

in order to clarify the deformation and failure mechanism of ret.ining structure ground under liquefying, a series of shaking table tests was performed. the test results suggest that the strength decrease and local liquefaction of subsoil are the leading factors in the deformation and failure of ret.ining structures. the movement of the ground mainly manifests the lateral displacement under liquefaction. At the backfill layer, liquefaction will be rapidly reached in far field whereas the excess pore pressure is slowly increased nearby the wall under shaking.

关键词： ret.ining structure simulating test ground liquefaction.

Machine learning enabled identification and real-time prediction of living plants’ stress using terahertz waves

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Defence technology（防务技术） 2022年第8期18卷 1330-1339页

作者： Adnan Zahid Kia Dashtipour Hasan t.Abbas ismail Ben Mabrouk Muath Al-Hasan Aifeng Ren Muhammad A.imran Akram Alomainy Qammer H.Abbasi School of Engineering and Physical Science Heriot-Watt UniversityEdinburghEH144ASUK James Watt School of Engineering University of GlasgowGlasgowG128QQUK College of Engineering Al-Ain UniversityAbu DhabiUnited Arab Emirates School of Electronic Engineering Xidian UniversityXi'anShaanxiChina School of Electronic Engineering and Computer Science Queen Mary University of LondonLondonUK

Considering the ongoing climate transformations, the appropriate and reliable phenotyping information of plant leaves is quite significant for early detection of disease, yield improvement. in real-life digital agricultural environment, the real-time prediction and identification of living plants leaves has immensely grown in recent years. Hence, cost-effective and automated and timely detection of plans species is vital for sust.inable agriculture. t.is paper presents a novel, non-invasive method aiming to establish a feasible, and viable technique for the precise identification and observation of altering behaviour of plants species at cellular level for four consecutive days by integrating machine learning (ML) and tHz with a swissto12 materials characterization kit (MCK) in the frequency range of 0.75 to 1.1 tHz. For t.is purpose, measurements observations data of seven various living plants leaves were determined and incorporate three different ML algorithms such as random forest (RF), support vector machine, (SVM), and K-nearest neighbour (KNN). the results demonstrated that RF exhibited higher accuracy of 98.87% followed by KNN and SVM with an accuracy of 94.64% and 89.67%, respectively, for precise detection of different leaves by observing their morphological features. in addition, RF outperformed other classifiers for determination of water-stressed leaves and having an accuracy of 99.42%. it.is envisioned that proposed study can be proven beneficial and vital in digital agriculture technology for the timely detection of plants species to significantly help in mitigate yield and economic losses and improve crops quality.

关键词： terahertz sensing Plants health Machine learning

Production of Nanopowders of Platinum Metals Using the Chemical Reduction Method

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贵金属 2012年第A1期33卷 267-268页

作者： PYAtAKHiNA E. S. BUSLAYEVA t. M. VOLCHKOVA E. V. KHRiStiCH E. A. ERGEYEVA t. Yu. OJSC "SiC 'Supermetal'" Moscow Russia Lomonosov Moscow University of Fine Chemical technology Moscow Russia.

the literary data on the application of various methods for the production of nanopowders of platinum metals and alloys have been summarized, and the selection of the method of chemical reduction from salt solutions has been substantiated as the simplest and most affordable. the optimum conditions for the production of nanoparticles of metal palladium and platinum/cobalt alloy, using the effect of boranes with various structures, have been selected.

关键词： platinum metals powders double complex salts reduction boranes