检索结果-南通市图书馆

Unveiling the Optimal Interfacial Synergy of Plasma-Modulated Trimetallic Mn-Ni-Co Phosphides:Tailoring Deposition Ratio for Complementary Water Splitting

引用

energy & environmental Materials 2023年第2期6卷 129-141页

作者： kholoud e.salem Amina A.Saleh Ghada e.Khedr Basamat S.Shaheen Nageh K.Allam energy Materials Laboratory(eML) School of Sciences and EngineeringThe American University in CairoNew Cairo 11835Egypt

Designing highly active,durable,and nonprecious metal-based bifunctional electrocatalysts for overall water electrolysis is of urgent scientific importance to realize the sustainable hydrogen production,which remains a grand ***,an innovative approach is demonstrated to synthesize flower-like 3D homogenous trimetallic Mn,Ni,Co phosphide catalysts directly on nickel foam via electrodeposition followed by plasma *** electrochemical activity of the catalysts with varying Mn:Ni:Co ratios is assessed to identify the optimal composition,demonstrating that the equimolar trimetallic phosphide yields an outstanding HeR catalytic performance with a current density of 10 mA cm^(-2) at an ultra-low overpotential of~14 mV,outperforming the best reported *** is asserted by the DFT calculations,revealing strong interaction of the metals and the P atom,resulting in enhanced water activation and optimized G_(H)^(*)values for the HeR ***,this optimal composition appreciably catalyzes the OeR by exposing more intrinsic active species in-situ formed on the catalyst surface during the ***,the Mn_(1)-Ni_(1)-Co_(1)-P-(O)/NF catalyst exhibits a decreased overpotential of~289 mV at 10 mA cm^(-2).More importantly,the electrocatalyst sustains perfect durability up to 48 h at a current density of 10 mA cm^(-2) and continued 5000 cycling stability for both HeR and ***,the assembled MNC-P/NF||MNC-P/NF full water electrolyzer system attains an extremely low cell voltage of 1.48 V at 10 mA cm^(-2).Significantly,the robust stability of the overall system results in a remarkable current retention of~96%after a continuous 50-h ***,this study provides a facile design and a scalable construction of superb bifunctional ternary MNC-phosphide electrocatalysts for efficient electrochemical energy production systems.

关键词： DFT overall water splitting oxygen evolution reaction(OeR)/hydrogen evolution reaction(HeR) plasma ternary metallic phosphides(MnNiCo)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Impact of Initial electron Development on Sodium Plasma Generation Using LIBORS Technique: Numerical Modeling

引用

Journal of Modern Physics 2018年第4期9卷 669-684页

作者： kholoud A. Hamam Yosr e. e.-D. Gamal Department of Physics Faculty of Science King Abdulaziz University Jeddah KSA National Institute of Laser enhanced Sciences Cairo University El Giza Egypt

The present work reports an investigation on the role played by Na3+ ions formed through triatomic associative ionization collision of Na(4d) atoms with Na2 ground state molecules during the early phase of sodium plasma generation by laser ionization based on resonance saturation (LIBORS). Such ionization mechanism is observed experimentally for the first time by Tapalian and Smith (1993) [1]. In their experiment, stepwise atomic excitations are created using two CW dye lasers;one laser is tuned to 589 nm to excite the Na(3s) to Na(3p) D2 transition of sodium and the other laser is tuned 569 nm to excite the Na(3p) to Na(4d) transition. The analysis is grounded on a numerical study of the role of seed electron processes on the temporal evolution of sodium plasma formation by laser irradiation. A previously developed numerical model based on LIBORS technique is modified and adopted. In the present study, the sodium atom is treated as an atom comprises 22 levels namely: a ground state, 18 excited states and three ionic states (atomic, molecular and tri-atomic). The model tackled various collisional and radiative processes that act to enhance and deplete the free electrons generated in the interaction region. The contribution of these processes is signified by solving numerically a system of time-dependent rate equations, which couple the generated atomic and ionic species with the laser fields. Meanwhile, it solves the time-dependent Boltzmann equation for the electron energy distribution function (eeDF) of the generated electrons. The computed values of the eeDF, time evolution of both excited states population and the formed ionic species considering the individual effect of associative ionization, Penning, and photo-ionization and triatomic associative ionization justified the important effect of each of these ionizing processes in creating the early stage electrons. These seed electrons are assumed to rapidly gain energy through superelastic collisions leading eve

关键词： Plasma Laser Collisional Ionization Association Ionization Tri-Atomic Ions Photoionization electron energy Distribution Function

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Numerical Study of the Threshold Intensity Dependence on Wavelength in Laser Spark Ignition of Molecular Hydrogen Combustion

引用

Journal of Modern Physics 2013年第3期4卷 311-320页

作者： kholoud A. Hamam Galila Abdellatif Yosr e. e.-D. Gamal Department of physics Girl’s Faculty of Science King Abdul-Aziz University Jeddah KSA. National Institute of Laser enhanced Science-Cairo University El-Giza Egypt. Physics Department Faculty of Science Cairo University Giza Egypt

A numerical investigation of laser wavelength dependence on the threshold intensity of spark ignition in molecular hydrogen over a wide pressure range is presented. A modified electron cascade model (Gamal et al., 1993) is applied under the experimental conditions that carried out by Phuoc (2000) to determine the threshold intensity dependence on gas pressure for spark ignition in hydrogen combustion using two laser wavelengths namely;1064 nm and 532 nm. The model involves the solution of the time dependent Boltzmann equation for the electron energy distribution function (eeDF) and a set of rate equations that describe the change of the formed excited molecules population. The model takes into account most of the physical processes that expected to occur in the interaction region. The results showed good agreement between the calculated thresholds for spark ignition and those measured ones for both wavelengths, where the threshold intensities corresponding to the short wavelength (532 nm) are found to be higher than those calculated for the longer one (1064 nm). This result indicates the depletion of the high density of low energy electrons generated through multi-photon ionization at the short wavelength via electron diffusion and vibrational excitation. The study of the eeDF and its parameters (viz, the temporal evolution of: the electron density, ionization rate electron mean energy, …) revealed the important role played by each physical process to the spark ignition as a function of both laser wavelength and gas pressure. More over the study of the time variation of the eeDF explains the characteristics of the ignited spark at the two wavelengths for the tested pressure values.

关键词： Laser Wavelength Hydrogen Gas Threshold Intensity electron energy Distribution Function Combustion Spark Ignition

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Amblyopia screening for first and second-grade children in Jordan

引用

International Journal of Ophthalmology(english edition) 2022年第2期15卷 352-356页

作者： Khalil M.Al-salem Mohammad S.Saleem Ismat ereifej Hamzeh M.Alrawashdeh Rayed Falah Hussein Obeidat Asma Ali Abdlmohdi Raeda Zaki Al-Momani Layal Mohammed Hammad Omar Ahmad al-Habahbeh Yaqeen M.Assassfeh Laith Ramzi Najib Al-Qsous Ashraf Hatim Adeeb Nasraween Tariq A.Al Maaitah Deya'-Aldin Muneer Hasan Aqeel Ibtehal eyadeh Awad Alabdulrazzg Abdullah Mahmoud Mohammad Murad Amany Jehad Faleh AL-Zurqan enas Jamal Mohammad Jaradat Slsabela emad Suliman Aldhoon Ala'a Majed Dmour Ahmad Talal Asassfeh Jeries Ayman Halaseh Abdel Aziz Ammar Daoud Waha Ayman Alkasasbeh kholoud GH.Matar Department of Ophthalmology and Visual Sciences Mutah UniversityAl-Karak 11183Jordan Royal Medical Services Department of Ophthalmology Amman 11855Jordan Department of Ophthalmology and Visual Sciences Al-Sharif Eye CenterAmman 11194Jordan Jordanian Menistrery of Health IrbidAmman 11855Jordan National Woman's Health Care Center(NWHCC) Amman 11855Jordan

AIM:To share the results of a national screening program for amblyopia in school children in the north of ***:This is a prospective national screening study for *** program rolls first and second-grade children(6 to 7 years old) in the north of *** eye examination included:best-corrected visual acuity,cover-uncover test,and cycloplegic *** visual acuity was tested using an eTDRS visual acuity chart without ***,children were tested with full cycloplegic refraction when the test criteria were *** amblyopia was defined as a best-corrected visual acuity difference of 2 or more *** comparison,bilateral amblyopia was defined as a best-corrected visual acuity of 20/40 or worse in the best ***:The prevalence of amblyopia for the total sample tested(n=17 203) was 2.78%(n=479).The most common cause of amblyopia was hypermetropia(64.45%),followed by previous ocular surgeries(15.1%),myopia(10.43%),strabismus(9.39%),and congenital cataract(0.63%).CONCLUSION:This is the first and only study,identifing modifiable risk factors in Jordanian children with *** their first couple of years of elementary education,many Jordanian children are affected by amblyopia and pass unnoticed.A more governmental effort is needed into screening programs to improve vision in the Jordanian population.

关键词： amblyopia screening Jordan community ophthalmology pediatric ophthalmology population-based study screening program

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Tobacco use among population sub-groups: A gender analysis

引用

Open Journal of Preventive Medicine 2012年第4期2卷 468-477页

作者： Ahmed Mandil Sahar Abdel Maqsoud kholoud Tayel Mona Shama epidemiology Department High Institute of Public Health [HIPH] Alexandria University Alexandria Egypt Family Health Department High Institute of Public Health University of Alexandria Alexandria Egypt Health education Department High Institute of Public Health University of Alexandria Alexandria Egypt Preventive Affairs Department Alexandria University Students’ Clinic and Hospital Alexandria Egypt

Women comprise 20% of world’s billion smokers. especially troubling is raising prevalence of tobacco use among girls. In fact, it is expected that 20% of women in developing/developed countries will be smokers by 2025. This study analytically compares knowledge, attitudes, and practices of tobacco use, by gender, among 4 sub-populations in Alexandria, egypt. Methods: A cross sectional approach was used for 4 subgroups (high school students, university students, shopping malls/clubs’ attendees, employees of health-related facilities), 1000 each (total sample size = 4000). A modified version of WHO questionnaire was used for data collection. Results: Smoking prevalence was generally higher among males (29%-44%) compared to females (2% - 9%) in the studied groups. Cafeterias were preferable smoking places for both genders, especially among high school/university students. Most smokers in the 4 subgroups reported that most or all their friends were smokers. Mean knowledge scores were found to be higher among male employees/high school students, compared to females in the same sub-groups. Mean attitude scores towards smoking were higher among females (i.e. against smoking) in the 4 sub-samples. Conclusion & Recommendations: Tobacco use among males is generally higher among males, but females seem to be catching up. Social gatherings seem to attract many youngsters, of both genders, to smoke in public, especially waterpipe (which is a growing epidemic of tobacco use in our communities). Mass community- and gender-based health awareness campaigns are needed, using different channels, including school-based health education interventions, at the earliest age possible.

关键词： Tobacco Use Gender Analysis Population Sub-Groups

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

experimental investigation of colloid formation and cesium mobility in Hanford sediment columns

引用

Chinese Journal Of Geochemistry 2006年第B8期25卷 85-85页

作者： Ziya S. Cetiner kholoud Mashal Markus Flury James B. Harsh Canakkale 18 Mart University Department of Geological Engineering Canakkale 17020 TURKEY Hashemite University Department of Land Management and Environment Zarqa 13115 JORDAN Department of Crop and Soil Sciences Center for Multiphase Environmental Research Washington State University Pullman Washington 96164-6420 USA

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：