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Synthesis and Characteristics of Conducting Polymer- Based Polypyrrole in Different Solvents

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材料科学与工程（中英文A版） 2012年第2期2卷 190-195页

作者： Nurhizwati Abd Rahman Tunku Ishak Tunku Kudin Malik Marwan Ali Muhd Zu Azhan yahya Ionic Materials ＆ Devices （iMADE） Research Laboratory Faculty of Applied Sciences Universiti Teknologi MARA 40450 ShahAlam Malaysia

Polypyrrole (PPy) was synthesized under dry nitrogen atmosphere by chemical polymerization. The oxidant agent, ferric chloride, was mixed with several types of solvents, such as hydrochloric acid, deionized water, and acetonitrile, before the monomer pyrrole was added. The resultant precipitate was filtered and rinsed with methanol and ethanol several times and dried in vacuum oven at 40 °C for over 12 h. Conductivity tests, x-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy were carried out to investigate the structure and morphology of PPy. The conductivity of the prepared samples was studied in the frequency range 100 hz to 1 Mhz over the temperature range 253-393 K. The degree of surface density of PPy powder was directly related to its dependence on solvents, which can be represented via the following: h2O > ACN > hCl.

关键词：混合溶剂聚合合成聚吡咯导电聚合物傅里叶变换红外光谱扫描电子显微镜特性基础

节点域加强的h型钢柱与中、宽翼缘h型钢梁的盖板加强型连接的滞回性能研究

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节点域加强的H型钢柱与中、宽翼缘H型钢梁的盖板加强型连接的滞回...

作者：吴萨（Osama Zaid yahya Al-ansi）长安大学

学位级别：硕士

在北岭地震和神户地震中,传统的钢框架梁柱节点产生了大量的脆性裂缝。研究表明:焊接裂纹限制了梁柱节点的塑性发展,不能有效的消耗地震能量。在以往的研究中,梁都是通用的梁截面,即带窄翼缘的工字钢,但有时窄翼缘工字梁不符合设计要求... 详细信息

在北岭地震和神户地震中,传统的钢框架梁柱节点产生了大量的脆性裂缝。研究表明:焊接裂纹限制了梁柱节点的塑性发展,不能有效的消耗地震能量。在以往的研究中,梁都是通用的梁截面,即带窄翼缘的工字钢,但有时窄翼缘工字梁不符合设计要求,用中翼缘工字梁代替窄翼缘工字梁是一个很好的选择。然而,关于这种梁柱连接的研究较少,为了进一步探讨中翼缘工字梁框架节点在循环荷载作用下的力学性能,借助ABAQUS软件,本文进行了中翼缘工字梁框架节点在循环荷载作用下,带加强区盖板与加强节点滞回性能的研究。在有限元中通过对结合点的变参,研究了结合点的破坏机理和关键因素;研究了焊缝应力分布;研究了刚度与延性的匹配等问题;同时,本研究也针对节点的不足进行了改进研究,工作和结论如下:·通过对钢梁柱节点试验的模拟,证明了本文所采用的ABAQUS有限元模拟方法具有较高的精度和可靠性。·通过盖板加强节点与标准节点的对比分析,得出结论:盖板加强节点的承载力、延性系数、塑性转动能力均优于标准节点。·按钢梁尺寸将试件分为三组:hW350×350×12×19、hM390×300×10×16和hM340×250×9×14。三组试件均为hW502×470×20×25柱(高3600mm)、大跨度梁(3000mm)。结果表明,该梁翼缘较宽,具有较好的延性和变形能力。此外,第一组节点的初始转动刚度显著提高,节点的转动变形也较其他两组减小。·结果表明,盖板形状对节点应力分布影响不大。盖板的长度和厚度越大,节点的转动刚度越高,但会导致梁端塑性铰向外移动,降低节点的塑性转动能力。·盖板长度和厚度对节点的抗震性能有明显的影响。当盖板长度和厚度取梁翼缘截面高度和厚度的0.5倍时,节点具有较大的刚度和延性。

关键词：强轴连接盖板循环荷载 ABAQUS 有限元模拟塑性铰

Electromagnetic Response Studies of the Antenna for Deep Water Deep Target CSEM Environments

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Journal of Electromagnetic Analysis and Applications 2012年第12期4卷 513-522页

作者： Noorhana yahya Nadeem Nasir Majid Niaz Akhtar Muhammad Kashif Tanvir hussain hasnah Mohd Zaid Afza Shafie Electrical and Electronic Engineering Department Tronoh Malayia Electrical and Electronic Engineering Department Tronoh Malayia 3Fundamental and Applied Science Department National Textile University Faisalabad Pakistan Fundamental and Applied Science Department Tronoh Malayia Fundamental and Applied Science Department Tronoh Malayia 2Electrical and Electronic Engineering Department Tronoh Malayia Mechanical Engineering Department Universiti Teknologi PETRONAS Tronoh Malaysia.

The Controlled Source Electromagnetic Method (CSEM) is used for offshore hydrocarbon exploration. hydrocarbon detection in seabed logging (SBL) is a very challenging task for deep hydrocarbon reservoirs. The electromagnetic field response of an antenna is unable to detect deep hydrocarbon reservoirs due to a weak electromagnetic signal response in the seabed logging environment. This work premise deals with the comparison of the electromagnetic signal strength of a new antenna with a straight antenna and the orientation of an antenna for deep target hydrocarbon exploration. Antenna position and orientation (Tx and Ty) was studied using Computer Simulation Technology software (CST) for deep targets in marine CSEM environments. The model area was assigned as (40 ′ 40 km) to replicate the real seabed environment. From the results, the new dipole antenna shows an 804% and 278% increase in electric and magnetic field strength than the straight antenna. An electric (E) and magnetic (h) field component study was done with and without the presence of a hydrocarbon reservoir. Ex and hz field component responses with the new antenna at the1 kmtarget were measured in a deep water environment. It was analyzed that the antenna shows 53.10% (Ex) and 83.13% (hz) field difference in deep water with and without a hydrocarbon reservoir at the30 mantenna position from the sea floor. From the antenna orientation results, it was observed that, the electric field Ex and magnetic field hz responses decreased from 18% to 12% and 21% to 16%, respectively but was still able to detect the deep target hydrocarbon reservoir at the4 kmtarget depth. This EM antenna may open new frontiers for the oil and gas industry for deep target hydrocarbon detection (hC).

关键词： Control Source Electromagnetic (CSEM) Seabed Logging (SBL) Antenna Computer Simulation Technology (CST) hydrocarbon (hC)

Evaluation of the Influence of Fixed Orthodontic Treatment Duration on the Severity of Inflammatory Gingival Enlargement (Fixed Orthodontic Induced Gingival Enlargements) and Some Properties of Saliva

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International Journal of Clinical Medicine 2022年第3期13卷 132-146页

作者： Mohammed M. A. Abdullah Al-Abdaly Abdullah Mohammed A. Asiri Ghadeer Mohammed Mohammed Al-Abdaly Mohammed Abdullah Ghabri Moayad Abdullah h. Alqaysi Abdulmajeed Mohammed S. Aljathnan yahya Saleem M. Al Naser Naser Ali N. Alshahrani Periodontics and Community Dental Sciences Department College of Dentistry King Khalid University Abha KSA College of Dentistry King Khalid University Abha KSA Faculty of Dentistry Sana’a University Sanaa Republic of Yemen

Background: Inflammatory gingival enlargement is a more common clinical feature with orthodontic therapy than other features. Therefore, this study was designed to the evaluation of the influence of fixed orthodontic treatment duration on the severity of inflammatory gingival enlargement (fixed orthodontic induced gingival enlargements) and some properties of saliva. Material and Methods: The sample size comprised 145 patients undergoing fixed orthodontic treatment for at least 6 months aged 13 - 32 years. They were divided according to orthodontic treatment duration into three groups. Group I (n = 47) included the patients who were treated for less than 6 months, group II (n = 51) included the patients who were treated for a period of 6 - 12 months, and group III (n = 47) included the patients who were managed for more than 12 months. Data were obtained from the outpatient clinics, college of dentistry, King Khalid University, Abha, Saudi Arabia, and some dental centers in Sana’a city, the Republic of Yemen. This study was conducted from October 2021 G to January 2022 G. Clinical examination was done for plaque index (PLI), gingival index (GI), and gingival enlargement indexes (GEI). Saliva was collected in sterile test tubes then salivary flow and ph were measured. Statistical analysis was done with SPSS (version 23) and ANOVA test to evaluate the impact of orthodontic treatment duration on the severity of inflammatory gingival enlargement and some properties of saliva. Results: The statistical analysis demonstrated the highest mean plaque index (PLI) was among groups III and I participants whereas, the highest mean gingival index and mean gingival enlargement were among groups II and III participants. The present study revealed an increase in salivary flow with decreased salivary ph values with an increase in orthodontic therapy duration. There were statistically significant differences in clinical findings and salivary flow and ph values were observed in the com

关键词： Inflammatory Gingival Enlargement Orthodontic Treatment Duration Some Salivary Properties

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颅脑损伤与胰岛素抵抗的相关性研究

中国临床神经外科杂志 2007年第3期12卷 146-148页

作者：施恩标崔华张健 humaid yahya 费智敏周正文书国伟李善泉王勇上海交通大学医学院附属仁济医院崇明分院神经外科上海202150 上海交通大学医学院附属仁济医院神经外科上海200001

目的分析颅脑损伤的严重性、血糖与胰岛素水平三者之间的关系。方法92例颅脑损伤患者按入院时GCS评分分为轻度、中度及重度颅脑损伤三组,分别于伤后24h、48h、72h测定空腹血糖、血清胰岛素值,并计算稳态模式中的胰岛素抵抗指数(hOMA-IR... 详细信息

目的分析颅脑损伤的严重性、血糖与胰岛素水平三者之间的关系。方法92例颅脑损伤患者按入院时GCS评分分为轻度、中度及重度颅脑损伤三组,分别于伤后24h、48h、72h测定空腹血糖、血清胰岛素值,并计算稳态模式中的胰岛素抵抗指数(hOMA-IR)。患者出院时按GOS标准评估预后。采用SPSS11.5统计软件对数据进行处理,分析GCS、空腹血糖、胰岛素水平的关系。结果出院时按GOS标准,良好72例,差12例,死亡8例,死亡率8.7%。92例颅脑损伤患者伤后连续3d空腹血糖及胰岛素水平在轻度、中度、重度颅脑损伤三组患者中有显著差异(PhOMA-IR越高。结论空腹血糖值和hOMA-IR值可作为评估颅脑损伤严重程度的参考指标。

关键词：颅脑损伤胰岛素抵抗高血糖

Effect of Rice AUXIN BINDING PROTEIN57(OsABP57)Overexpression in Response to Flooding

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Journal of Agricultural Science and Technology(B) 2020年第3期10卷 125-133页

作者： Zarith Ayunie Zambrose Sitti Aisyah Mohd Roszelin Nur Aminah Binti Mohd hazbir Bee Lynn Chew Siti Sarah Jumali Wan Asrina Wan yahya Nurulhikma Md Isa Department of Biological Sciences and Biotechnology Faculty of Science and TechnologyUniversiti Kebangsaan MalaysiaUKM Bangi 43600SelangorMalaysia School of Biological Sciences Universiti Sains MalaysiaMinden 11800GeorgetownPenangMalaysia Faculty of Plantation and Agrotechnology UiTM Melaka BranchMerlimau 77300MelakaMalaysia Department of Crop Science Faculty of Agriculture and Food SciencesUniversiti Putra MalaysiaSarawak CampusBintulu 97008Sarawak

This study reports the effects of Oryza sativa AUXIN BINDING PROTEIN57(OsABP57)overexpression towards flooding in ***57 was previously reported to activate plasma membrane h+-*** studies address the ability of transgenic OsABP57 overexpression in enduring drought and salinity stresses but none on the *** this study,complete submergence analysis was carried out and several morphophysiological parameters were analyzed such as plant height,root architecture and relative chlorophyll *** showed that there are no differences between OsABP57 overexpression rice compared to MR219 control rice in terms of chlorophyll content and plant height after 1-3 weeks of flooding *** analysis,however,found that transgenic rice OsABP57 produced more adventitious roots compared to MR219 rice under normal condition,which may be due to the role of the gene that encodes for auxin binding *** semi-quantitative polymerase chain reaction(PCR)on Oryza sativa pyruvate decarboxylase(OsPDC)gene after two weeks of flooding treatment showed an increase of expression in OsABP57 transgenic compared to ***,the overexpression of OsABP57 did not show any significant difference in terms of morphophysiological analysis between the transgenic line and MR219,yet,there is an increase of OsPDC gene in the transgenic background which may need further experimental analysis in the future to map the network between auxin and hypoxia core genes.

关键词： Oryza sativa flooding OsABP57 MR219 hypoxia.