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排序方式: 共有363条查询结果,搜索用时 15 毫秒
1.
F.T. Munna Vidhya Selvanathan K. Sobayel Ghulam Muhammad Nilofar Asim Nowshad Amin Kamaruzzaman Sopian Md. Akhtaruzzaman 《Ceramics International》2021,47(8):11003-11009
In this study, dilute chemical bath deposition technique has been used to deposit CdZnS thin films on soda-lime glass substrates. The structural, morphological, optoelectronic properties of as-grown films have been investigated as a function of different Zn2+ precursor concentrations. The X-ray diffractogram of CdS thin-film reveals a peak corresponding to (002) plane with wurtzite structure, and the peak shift has been observed with the increase of the Zn2+ concentration upon formation of CdZnS thin film. From morphological studies, it has been revealed that the diluted chemical bath deposition technique provides homogeneous distribution of film on the substrate even at a lower concentration of Zn2+. Optical characterization has shown that the transparency of the film is influenced by Zn2+ concentration and when the Zn2+ concentration is varied from 0 M to 0.0256 M, bandgap values of resulting films range from 2.42 eV to 3.90 eV while. Furthermore, electrical properties have shown that with increasing zinc concentration the resistivity of the film increases. Finally, numerical simulation validates and suggests that CdZnS buffer layer with composition of 0.0032 M Zn2+ concentration would be a promising candidate in CIGS solar cell. 相似文献
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BACKGROUND AND STUDY AIMS: Recently, attention has been drawn to the significant occurrence of respiratory and other complications during upper intestinal endoscopy. This prospective study was designed to compare the incidence and severity of oxygen desaturation when two different methods of oxygen delivery were used during elective oesophagogastroduodenoscopy. PATIENTS AND METHODS: After local medical ethics committee approval and written informed consent, one hundred patients undergoing elective oesophagogastroduodenoscopy were randomly allocated to receive supplemental oxygen at either four litres per minute via nasal specular or ten litres per minute through a specially modified non-rebreathing mask. Oxygen saturations during endoscopy facilitated by midazolam sedation were recorded, and non-parametric tests were used to compare the oxygen saturations in the two groups. RESULTS: The mean oxygen saturations were significantly better during the procedure for American Society of Anesthesiology (ASA) grade 2 and 3 patients who received oxygen with the modified mask than for those who received oxygen via nasal specular (98.6% vs. 97.0%, P = 0.004 for ASA grade 2 and 98.4% vs. 95.5, P = 0.006 for ASA grade 3). CONCLUSIONS: For ASA grade 2 and 3 patients, the modified non-rebreathing mask significantly improves oxygen saturations during upper intestinal endoscopy. This technique should be more widely used for patients at moderate and high risk. 相似文献
5.
Asim Muhammad Nabeel Ghani Muhammad Usman Ibrahim Muhammad Ali Mahmood Waqar Dengel Andreas Ahmed Sheraz 《Neural computing & applications》2021,33(11):5437-5469
Neural Computing and Applications - In order to provide benchmark performance for Urdu text document classification, the contribution of this paper is manifold. First, it provides a publicly... 相似文献
6.
Shaikh Mohd Rizwan Uddin Loan Sajad A. Alharbi Abdullah G. 《Journal of Computational Electronics》2021,20(6):2360-2368
Journal of Computational Electronics - In this work, a Schottky junction on the drain side employing low workfunction (WF) metal is proposed as a method to suppress the OFF-state leakage in... 相似文献
7.
Epidemiological studies suggest the existence of a strong relationship between the incidence of prostatic cancer and the intake
of dietary lipids in humans. However, very little information is available on intracellular fatty acid metabolism in human
prostatic tissue. The objective of this study was to identify and subsequently characterize a fatty acid binding protein of
human prostatic tissue. A fatty acid binding protein (FABP) was purified and characterized from human prostatic tissue. The
purified FABP had an apparent molecular mass of 15.0±1.0 kDa as averaged from three different methods, sodium dodecylsulfate-polyacrylamide
gel electrophoresis (SDS-PAGE), gel filtration and amino acid analysis. The pI value of the protein was determined to be 6.8.
Scatchard analysis of fatty acid binding to the purified FABP from malignant prostatic tissue showed a Kd value of 0.53±0.02
μM for arachidonic acid (n=5). The Kd values of FABP purified from benign prostatic tissue were 0.57±0.02 μM for oleic acid
and 0.51±0.04 μM for arachidonic acid (n=5). Fatty acid analysis revealed that the level of endogenously bound arachidonic
acid was about 2.5-fold higher in FABP from malignant than from benign tissue. In addition, both malignant and benign tissues
contained the same concentration of FABP. The concentrations of FABP in malignant and benign tissues were 19.2±1.8 and 21.4±2.1
μg per mg of total cytosolic protein, respectively. Characterization based on amino acid composition, isoelectric point and
fluorescence with dansyl undecanoic acid suggests that the FABP may not be of the heart type, but is rather more closely related
to the liver type. As malignant prostatic tissue produces more PGE2 compared to benign tissue, our data suggest that FABP may help enhancing the synthesis of the prostaglandin in malignant
tissue by facilitating arachidonic acid transport.
A preliminary account of this work was presented at the Biochemical Society Meeting, London, December 16–18, 1991, and published
as an abstract (Ref. 1). 相似文献
8.
Simultaneous surface modification by 3‐chloropropyl and methyl groups on the same Si atoms resulted in hydrophobic and highly
ordered mesoporous silica with a very high surface area. 13C and 29Si MAS NMR spectra indicate homogeneous grafting of chloropropyl and methyl groups in the silica matrix and this organically
modified Ti‐MCM‐41 shows outstanding catalytic performance in the epoxidation of cyclododecene using tert‐butyl hydroperoxide
as oxidant.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
Dyeing cotton with reactive dyes under neutral conditions 总被引:1,自引:0,他引:1
This paper describes a new method to dye cotton with selected reactive dyes by long-liquor – or so-called 'exhaustion'– processes under neutral conditions. Particularly promising results were obtained with reactive dyes containing free vinyl sulphone residues. Although there are dyes on the market that contain free vinyl sulphone groups, for example, the Novacron C (Huntsman) range of dyes, many of this class contain 'blocked' vinyl sulphone residues; examples include sulphatoethylsulphone or chloroethylsulphone precursor groups, and these may be preactivated to the highly reactive vinyl sulphone form simply by a mild alkali treatment. After this activation, neutral, long-liquor dyeings can be carried out at the boil in the presence of electrolyte. This new dyeing method gave very good results in terms of overall fixation efficiency values, without the need for alkali additions. 相似文献
10.
Reproducible Enhancement of Fluorescence by Bimetal Mediated Surface Plasmon Coupled Emission for Highly Sensitive Quantitative Diagnosis of Double‐Stranded DNA 下载免费PDF全文
Nhu Hoa Thi Tran Kieu The Loan Trinh Jun‐Ho Lee Won Jung Yoon Heongkyu Ju 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(32)
Plasmonic enhancement of fluorescence from SYBR Green I conjugated with a double‐stranded DNA (dsDNA) amplicon is demonstrated on polymerase chain reaction (PCR) products. Theoretical computation leads to use of the bimetallic (Au 2 nm–Ag 50 nm) surface plasmons due to larger local fields (higher quality factors) than monometallic (Ag or Au) ones at both dye excitation and emission wavelengths simultaneously, optimizing fluorescence enhancement with surface plasmon coupled emission (SPCE). Two kinds of reverse Kretschmann configurations are used, which favor, in signal‐to‐noise ratio, a fluorescence assay that uses optically dense buffer such as blood plasma. The fluorescence enhancement (12.9 fold at maximum) with remarkably high reproducibility (coefficient of variation (CV) < 1%) is experimentally demonstrated. This facilitates credible quantitation of enhanced fluorescence, however unlikely to obtain by localized surface plasmons. The plasmon‐induced optical gain of 46 dB due to SPCE‐active dye molecules is also estimated. The fluorescence enhancement technologies with PCR enables LOD of the dsDNA template concentration of ≈400 fg µL?1 (CV < 1%), the lowest ever reported in DNA fluorescence assay to date. SPCE also reduces photobleaching significantly. These technologies can be extended for a highly reproducible and sufficiently sensitive fluorescence assay with small volumes of analytes in multiplexed diagnostics. 相似文献