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Comparative Study of Structural, Optical and Electrical Properties of SnO<sub>2</sub>Thin Film Growth via CBD, Drop-Cast and Dip-Coating Methods
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作者 Md. Tareq Rahman zubair ahmed +6 位作者 Md. Johurul Islam Kamaruzzaman Mst. Toma Khatun Md. Abdul Gafur Md. Shahriar Bashar Md. Monjarul Alam 《Materials Sciences and Applications》 2021年第12期578-594,共17页
Tin oxide (SnO<sub>2</sub>) thin films were deposited on glass substrate by Chemical Bath Deposition (CBD), Drop-Cast and Dip-Coating method. The thin films were post-annealed at 500&deg;C for 2 hours.... Tin oxide (SnO<sub>2</sub>) thin films were deposited on glass substrate by Chemical Bath Deposition (CBD), Drop-Cast and Dip-Coating method. The thin films were post-annealed at 500&deg;C for 2 hours. The structural, optical, and electrical properties of the SnO<sub>2</sub> thin films were investigated by using XRD, FTIR, SEM, EDX, UV-Vis spectroscopy, and Electrometer experiment. The XRD patterns of SnO<sub>2</sub> thin films deposited on glass substrate by CBD method, Drop-Cast method and Dip-Coating method showed cubic, tetragonal and amorphous structures respectively. The FTIR spectrum exhibited the strong presence of SnO<sub>2</sub> with the characteristic vibrational mode of Sn-O-Sn. The SEM analysis was observed that the surface morphology of the thin films toughly depends on the deposition methods of the SnO<sub>2</sub> thin films. EDX measurement confirmed that the thin films are the composition of Tin (Sn) and Oxygen (O<sub>2</sub>). The optical band gap of SnO<sub>2 </sub>thin films deposited by CBD method, Drop-Cast method and Dip-Coating method is found to be 3.12 eV, 3.14 eV and 3.16 eV respectively. Thin films deposited by Dip-Coating method showed the highest band gap. The electrical results confirmed that the SnO<sub>2</sub> thin films are good conductors and pursued Ohm’s Law. These properties of the SnO<sub>2</sub> thin films brand are appropriate for application in solar cell assembly, gas sensor devices and transparent electrodes of panel displays. 展开更多
关键词 SnO2 Thin Film CBD Drop-Cast and Dip-Coating Method Electrical
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M-矩阵代数Riccati方程的一类改进的交替线性化隐式迭代法(英文) 被引量:3
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作者 关晋瑞 周芳 zubair ahmed 《数学杂志》 2019年第6期811-822,共12页
本文研究了M-矩阵代数Riccati方程的求解问题.基于交替线性化隐式迭代法,提出了一类改进的交替线性化隐式迭代法用于计算M-矩阵代数Riccati方程的最小非负解.在一定条件下证明了新方法的收敛性并给出最优参数表达式.数值实验表明,改进... 本文研究了M-矩阵代数Riccati方程的求解问题.基于交替线性化隐式迭代法,提出了一类改进的交替线性化隐式迭代法用于计算M-矩阵代数Riccati方程的最小非负解.在一定条件下证明了新方法的收敛性并给出最优参数表达式.数值实验表明,改进的方法在一定条件下是可行的. 展开更多
关键词 代数RICCATI方程 最小非负解 M-矩阵 ALI迭代法
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An Investigation into Infection Prevention and Control Practices among Close Contacts of COVID-19 Positive Cases Identified during Trace Test and Quarantine Activities at District Quetta (Unmatched Case-Control Study)
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作者 Muhammad Arif Abid Saeed +10 位作者 Muhammad Abdullah Ambreen Chaudhary Zakir Hussain Mirza Zeeshan Iqbal Baig zubair ahmed Khoso Mir Abdul Qadir Sheikh ahmed Saher Sultan Zahra Gauhar Ayesha Babar Kawish Ehsan Larik 《Open Journal of Epidemiology》 2021年第4期360-370,共11页
The second wave of COVID-19 pandemic has started globally, right now 220 countries are infected and a total of 71,351,695 confirmed cases and 1,612,372 deaths due to COVID-19 have been reported. Infection Prevention a... The second wave of COVID-19 pandemic has started globally, right now 220 countries are infected and a total of 71,351,695 confirmed cases and 1,612,372 deaths due to COVID-19 have been reported. Infection Prevention and Control (IPC) measures for COVID-19 all have proved vital in decreasing the transmission rates among the communities. <strong>Methodology:</strong> Unmatched Case-Control Study was conducted where cases were defined as “every PCR positive contact (symptomatic or asymptomatic) for any index case” similarly controls were defined as “every PCR negative contact (symptomatic or asymptomatic) for any index case who was home quarantined for 14 days based on suspicion by PDSRU team”. A simple random technique was used and 300 individuals were made part of this study. <strong>Results:</strong> The major findings of this study shows that PCR positive contacts poorly adopted certain COVID-19 IPC measures of interest in their daily life hence got infected. The odds for all the variables of interest were found to be statistically significant among cases as compared to controls like the odds for knowingly and intentionally contacted with a COVID-19 positive case was 13.7 times more among the PCR positive contacts as compare to PCR negative contacts (p = 0.00, C.I = 7.62 - 24.90), similarly, the odds of being a family member of the index COVID-19 case was 7.07 times more among the PCR positive contacts as compared to the PCR negative contacts (p = 0.00, C.I = 3.25 - 15.86). <strong>Conclusion:</strong> Before the development and availability of a vaccine, the only tools that can help prevent the spread of COVID-19 are IPC measures. 展开更多
关键词 COVID-19 IPC Measures Contact PCR PDSRU
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Risk of “On Job Non Compliance” towards Various COVID-19 Standard &Transmission Based Infection Prevention &Control Measures/Precautions among the Healthcare Workers Working in OPD Settings of Public Sector Tertiary Care Hospitals of Quetta Balochistan (Prospective Cohort Study)
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作者 Muhammad Arif Muhammad Abdullah +10 位作者 Abid Saeed Ambreen Chaudhary Zakir Hussain Ayesha Babar Kawish Mir Abdul Qadir Sheikh ahmed Saher Sultan zubair ahmed Khoso Zahra Gauhar Tahira Kamal Ehsan Larik 《Open Journal of Epidemiology》 2021年第4期390-401,共12页
<strong>Background:</strong> COVID-19 Pandemic is still circulating within the human population and proving to be a deadlier disease with a mortality rate ranging from 0.5% to 7%. Since COVID-19 is a highl... <strong>Background:</strong> COVID-19 Pandemic is still circulating within the human population and proving to be a deadlier disease with a mortality rate ranging from 0.5% to 7%. Since COVID-19 is a highly transmissible disease;there is always a probability for its outward spread towards the general public and community from the hospitals and healthcare facilities where they come to seek treatment. <strong>Methodology:</strong> A prospective cohort study design was used, considering the limited available resources and time—a total of 200 healthcare workers (including doctors, nurses, para-medical staff, janitorial staff, reception staff & pharmacists) working in the OPDs of the two major public sector hospitals of Quetta were made part of this study. The study participants were selected using a simple random sampling technique and selection was made from the daily attendance register. The study participants from “Hospital-A” were first of all educated and trained on various COVID-19 IPC measures later on various COVID-19-IEC materials;written in simple Urdu language, were displayed clearly everywhere in the OPD. Similarly, handwashing stations along with hand sanitizers/soaps and surgical face masks were also made available free of cost for all the study participants of Hospital-A. Moreover the importance and effectiveness of COVID-19 IPC measures were continuously announced in the OPD gallery of Hospital-A, these announcements used simple wording in local languages (<em>i.e.</em>, Urdu, Pashto, Balochi and Brahvi). On the other hand, in the OPD of “Hospital-B”, no such interventions were made. The study participants of both the hospitals were followed for one month and observations like which group showed more on-job noncompliance towards various COVID-19 IPC measures were recorded. The data was recorded on daily basis (from 1<sup>st</sup> May-to-31<sup>st</sup> May 2021) after observing the study participants for compliance towards using face masks, face shields, personal protective gowns, gloves, ha 展开更多
关键词 COVID-19 IPC Measures IEC & BCC Materials
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与M-矩阵相关的一类二次矩阵方程的新迭代法 被引量:1
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作者 关晋瑞 宋儒瑛 zubair ahmed 《应用数学》 CSCD 北大核心 2021年第1期1-7,共7页
本文研究与M-矩阵相关的一类二次矩阵方程的数值解法.这类方程源于马尔可夫链的带噪Wiener-Hopf问题,其解中具有实际意义的是M-矩阵解.通过简单的变换,将该二次矩阵方程转化为M-矩阵代数Riccati方程.提出一种新的迭代方法,并对其进行收... 本文研究与M-矩阵相关的一类二次矩阵方程的数值解法.这类方程源于马尔可夫链的带噪Wiener-Hopf问题,其解中具有实际意义的是M-矩阵解.通过简单的变换,将该二次矩阵方程转化为M-矩阵代数Riccati方程.提出一种新的迭代方法,并对其进行收敛性分析.数值实验表明,新的迭代方法是可行的,且在一定条件下比现有的一些方法更为有效. 展开更多
关键词 二次矩阵方程 M-矩阵 代数RICCATI方程 迭代法
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M-矩阵平方根的一类迭代法
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作者 关晋瑞 邵荣侠 zubair ahmed 《应用数学》 CSCD 北大核心 2022年第2期386-393,共8页
矩阵平方根在数学的许多应用中起着重要的作用.本文研究M-矩阵平方根的计算问题,提出一种计算正则M-矩阵平方根的迭代方法.首先将这个问题转化为M-矩阵代数Riccati方程,进而提出一种有效的方法来求解这个特殊的MARE.理论分析表明,该方... 矩阵平方根在数学的许多应用中起着重要的作用.本文研究M-矩阵平方根的计算问题,提出一种计算正则M-矩阵平方根的迭代方法.首先将这个问题转化为M-矩阵代数Riccati方程,进而提出一种有效的方法来求解这个特殊的MARE.理论分析表明,该方法在一定条件下是收敛的.数值实验表明该方法是可行的,且优于二项式迭代法. 展开更多
关键词 矩阵平方根 正则M-矩阵 代数RICCATI方程 二项式迭代
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