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961.
Ravikumar Ramakrishnaiah Sunil Babu Kotha Abdulaziz Abdullah Alkheraif Sree Lalita Celur Darshan Devang Divakar Fawad Javed 《应用光谱学评论》2016,51(10):799-821
Raman spectroscopy is rapidly moving from an experimental technique for the analysis of biological molecules to a tool for the real-time clinical diagnosis and in situ evaluation of the oral tissue in medical and dental research. The purpose of this study is to identify various applications of Raman spectroscopy, to evaluate the contemporary status, and to explore future directions in the field of dentistry. Several in-depth applications are presented to illustrate Raman spectroscopy in early diagnosis of soft tissue abnormalities. Raman spectroscopy allows researchers to analyze histological and biochemical composition of biological tissues. The technique not only demonstrates its role in the disclosure of dysplasia and malignancy, but also in performing guided biopsies, diagnosing sialoliths, and assessment of surgical margins. Raman spectroscopy is used to identify the molecular structures and their components to give substantial information about the chemical structure properties of these molecules. In this article, we acquaint the utilization of Raman spectroscopy in analyzing the soft tissues in relation to dentistry. 相似文献
962.
Dr. Yingxiang Ye Yi Xie Dr. Yanshu Shi Dr. Lingshan Gong Dr. Joshua Phipps Prof. Abdullah M. Al-Enizi Prof. Ayman Nafady Prof. Banglin Chen Prof. Shengqian Ma 《Angewandte Chemie (International ed. in English)》2023,62(21):e202302564
Developing adsorptive separation processes based on C2H6-selective sorbents to replace energy-intensive cryogenic distillation is a promising alternative for C2H4 purification from C2H4/C2H6 mixtures, which however remains challenging. During our studies on two isostructural metal–organic frameworks ( Ni-MOF 1 and Ni-MOF 2 ), we found that Ni-MOF 2 exhibited significantly higher performance for C2H6/C2H4 separation than Ni-MOF-1 , as clearly established by gas sorption isotherms and breakthrough experiments. Density-Functional Theory (DFT) studies showed that the unblocked unique aromatic pore surfaces within Ni-MOF 2 induce more and stronger C−H⋅⋅⋅π with C2H6 over C2H4 while the suitable pore spaces enforce its high C2H6 uptake capacity, featuring Ni-MOF 2 as one of the best porous materials for this very important gas separation. It generates 12 L kg−1 of polymer-grade C2H4 product from equimolar C2H6/C2H4 mixtures at ambient conditions. 相似文献
963.
Asif Hayat Muhammad Sohail Usama Anwar T. A. Taha H. I. A. Qazi Amina Zeeshan Ajmal Abdullah G. Al-Sehemi Hamed Algarni Ahmed A. Al-Ghamdi Mohammed A. Amin Arkom Palamanit W. I. Nawawi Emad F. Newair Yasin Orooji 《Chemical record (New York, N.Y.)》2023,23(1):e202200143
The increasing demand for searching highly efficient and robust technologies in the context of sustainable energy production totally rely onto the cost-effective energy efficient production technologies. Solar power technology in this regard will perceived to be extensively employed in a variety of ways in the future ahead, in terms of the combustion of petroleum-based pollutants, CO2 reduction, heterogeneous photocatalysis, as well as the formation of unlimited and sustainable hydrogen gas production. Semiconductor-based photocatalysis is regarded as potentially sustainable solution in this context. g-C3N4 is classified as non-metallic semiconductor to overcome this energy demand and enviromental challenges, because of its superior electronic configuration, which has a median band energy of around 2.7 eV, strong photocatalytic stability, and higher light performance. The photocatalytic performance of g-C3N4 is perceived to be inadequate, owing to its small surface area along with high rate of charge recombination. However, various synthetic strategies were applied in order to incorporate g-C3N4 with different guest materials to increase photocatalytic performance. After these fabrication approaches, the photocatalytic activity was enhanced owing to generation of photoinduced electrons and holes, by improving light absorption ability, and boosting surface area, which provides more space for photocatalytic reaction. In this review, various metals, non-metals, metals oxide, sulfides, and ferrites have been integrated with g-C3N4 to form mono, bimetallic, heterojunction, Z-scheme, and S-scheme-based materials for boosting performance. Also, different varieties of g-C3N4 were utilized for different aspects of photocatalytic application i. e., water reduction, water oxidation, CO2 reduction, and photodegradation of dye pollutants, etc. As a consequence, we have assembled a summary of the latest g-C3N4 based materials, their uses in solar energy adaption, and proper management of the environment. This research will further well explain the detail of the mechanism of all these photocatalytic processes for the next steps, as well as the age number of new insights in order to overcome the current challenges. 相似文献
964.
Catlow CR French SA Sokol AA Al-Sunaidi AA Woodley SM 《Journal of computational chemistry》2008,29(13):2234-2249
Computational techniques have been applied to study a broad range of chemical and physical properties of zinc oxide. Both interatomic-potential and density functional theory methods are used to investigate structural, thermodynamic, surface, and defect properties. We survey the structures and energies of nano-particulate zinc oxide. 相似文献
965.
Fulgide 1-E doped in polystyrene polymer films was heated at various annealing temperatures.Upon irradiation with UV light(366 nm),fulgide 1-E undergoes a conrotatory ring closure to the pink colored closed form 1-C.The later color was switched back to the original color when the films were irradiated with white light.The kinetics of photocoloration and photobleaching processes were followed spectrophotometrically by monitoring the absorbance of the ring closed product 1-C at itsλ_(max) of 525 nm.The fir... 相似文献
966.
Shukor MY Masdor N Baharom NA Jamal JA Abdullah MP Shamaan NA Syed MA 《Applied biochemistry and biotechnology》2008,144(3):283-291
A heavy-metal assay has been developed using bromelain, a protease. The enzyme is assayed using casein as a substrate with
Coomassie dye to track completion of hydrolysis of casein. In the absence of inhibitors, casein is hydrolysed to completion,
and the solution is brown. In the presence of metal ions such as Hg2+ and Cu2+, the hydrolysis of casein is inhibited, and the solution remains blue. Exclusion of sulfhydryl protective agent and ethylenediaminetetraacetic
in the original assay improved sensitivity to heavy metals several fold. The assay is sensitive to Hg2+ and Cu2+, exhibiting a dose–response curve with an IC50 of 0.15 mg l−1 for Hg2+ and a one-phase binding curve with an IC50 of 0.23 mg l−1 for Cu2+. The IC50 value for Hg2+ is found to be lower to several other assays such as immobilized urease and papain assay, whilst the IC50 value for Cu2+ is lower than immobilized urease, 15-min Microtox™, and rainbow trout. 相似文献
967.
Shukor MY Habib SH Rahman MF Jirangon H Abdullah MP Shamaan NA Syed MA 《Applied biochemistry and biotechnology》2008,149(1):33-43
A molybdate-reducing bacterium has been locally isolated. The bacterium reduces molybdate or Mo6+ to molybdenum blue (molybdate oxidation states of between 5+ and 6+). Different carbon sources such as acetate, formate,
glycerol, citric acid, lactose, fructose, glucose, mannitol, tartarate, maltose, sucrose, and starch were used at an initial
concentration of 0.2% (w/v) in low phosphate media to study their effect on the molybdate reduction efficiency of bacterium. All of the carbon sources
supported cellular growth, but only sucrose, maltose, glucose, and glycerol (in decreasing order) supported molybdate reduction
after 24 h of incubation. Optimum concentration of sucrose for molybdate reduction is 1.0% (w/v) after 24 h of static incubation. Ammonium sulfate, ammonium chloride, valine, OH-proline, glutamic acid, and alanine (in
the order of decreasing efficiency) supported molybdate reduction with ammonium sulfate giving the highest amount of molybdenum
blue after 24 h of incubation at 0.3% (w/v). The optimum molybdate concentration that supports molybdate reduction is between 15 and 25 mM. Molybdate reduction is optimum
at 35 °C. Phosphate at concentrations higher than 5 mM strongly inhibits molybdate reduction. The molybdenum blue produced
from cellular reduction exhibits a unique absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. The
isolate was tentatively identified as Serratia marcescens Strain Dr.Y6 based on carbon utilization profiles using Biolog GN plates and partial 16s rDNA molecular phylogeny. 相似文献
968.
Mehmet Emin Sengül Abdullah Menzek Ertan Sahin Mustafa Arik Nurullah Saracoglu 《Tetrahedron》2008,64(30-31):7289-7294
Norcaran-2,3,4,5-tetraoles were synthesized starting from methyl 1,3,5-cycloheptatriene-7-carboxylate in several steps. Norcaradiene endoperoxide is the key component; it was obtained by photooxygenation of methyl 1,3,5-cycloheptatriene-7-carboxylate. The other oxygen functionalities are introduced through epoxide ring opening and OsO4-hydroxylation reactions. 相似文献
969.
Eleven different wild-growing edible mushroom species collected from various regions of Turkey were analysed for their content of 137Cs, 40K, 226Ra and 232Th using a high-resolution gamma-ray spectrometry. Specific activities of 226Ra and 232Th were generally below detection limits. The specific activities of 137Cs and 40K ranged from 2.4+/-0.3 to 109.0+/-7.3 Bq kg-1 with a mean of 28.4+/-27.2 Bq kg-1 (dry matter) and 715.5+/-50.1 to 1779.0+/-163.7 Bq kg-1 with a mean of 1150.8+/-315.2 Bq kg-1 (dry matter), respectively. The mean annual effective dose of 137Cs and 40K through mushrooms were estimated to be (7.0+/-6.0)x10(-3) microSv and 0.13+/-0.03 microSv, respectively. The overall intake of 137Cs is quite low and no significant contamination was found in collected mushroom species. The highest contents of 137Cs and 40K among the analysed mushrooms were in Morchella esculenta and Stropharia coronilla, respectively. 相似文献
970.
Aziman Eli Syafiqah Ismail Aznan Fazli Jubri Siti Fatimah Rahmat Muhammad Abdullah Idris Wan Mohd Razi 《Journal of Radioanalytical and Nuclear Chemistry》2021,330(3):667-683
Journal of Radioanalytical and Nuclear Chemistry - Comprehensive radiological survey and evaluation of heavy metal contamination were conducted in Chini Lake, which has been awarded a pristine... 相似文献