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121.
Marble slurry derived hydroxyapatite as heterogeneous catalyst for biodiesel production from soybean oil 下载免费PDF全文
122.
Vinay Singh K. Uvanesh Rashmi Rekha Behera Samrat Baruah Tarun Agarwal Indranil Banerjee 《Polymer-Plastics Technology and Engineering》2016,55(9):879-888
This study discusses about the effect of polysaccharides (agar, gum tragacanth, and guar gum) on the properties of the core (organogel)–shell [poly(vinyl alcohol)] microparticles. The size, swelling, and mucoadhesive properties of the poly(vinyl alcohol) microparticles were altered in the presence of the polysaccharides. Thermal analysis confirmed the presence of organogels within the microparticles. Fourier transform infrared spectroscopy confirmed the presence of the polysaccharides within the microparticles. The microparticles were biocompatible in nature. Drug release indicated that an alteration in the shell composition can be used for altering drug release. Ciprofloxacin-loaded microparticles showed sufficient antimicrobial efficiency. 相似文献
123.
Suruchi Poddar Piyush Sunil Agarwal Ajay Kumar Sahi Neelima Varshney Kiran Yellappa Vajanthri Sanjeev Kumar Mahto 《应用聚合物科学杂志》2021,138(24):50569
The present study reports for first time the blending of psyllium husk (PH) powder/gelatin (G) in the polymer-rich composition of polyvinyl alcohol (PVA) to make an electrospinnable solution. The composite was prepared in 3 different ratios viz., 100% (wt/wt) (PVA + PH), 75% + 25% (PVA + 75PH + 25G) (wt/wt) and 50% + 50% (PVA + 50PH + 50G) (wt/wt) in 6% PVA solution. Optimum electrospinning parameters were evaluated for all the prepared blends. The fabricated nanofibers were characterized by scanning electron microscopy (SEM), attenuated total reflectance-Fourier transform infrared, differential scanning calorimetry, porosity percentage, and fiber orientation using ImageJ software. A qualitative in vitro degradation study at room temperature is supported by SEM images. The cellular interactions were characterized by MTT assay of NIH-3T3 fibroblast cells for 2 and 4 days with an optimum cell growth of >50% by fourth day of culture and long-term cultivation of L929-RFP cells was observed for 10 days. The nanofibers were formed in the range of 49–600 nm. PVA + 75PH + 25G when cultured with L929-RFP cells exhibited highest fluorescence intensity and thus supported cellular proliferation significantly. Based on the results obtained from various analyses, we anticipate that fabricated psyllium-based nanofiber can be used as a promising candidate for wound healing and other biomedical applications. 相似文献
124.
Amit Kumar Rajendra Prasad Badoni Shailey Singhal Shilpi Agarwal Amitabh Raj Tripathi 《Chemical Engineering Communications》2018,205(1):92-101
Sulfated zirconia is a very strong solid acid catalyst which can be utilized for various reactions. The present study focuses on synthesis of zirconia-based catalyst with high acidity and high surface area, particularly for isomerization reaction. Sulfated zirconia has been obtained by sulfation of zirconia prepared by hydrothermal route. The catalyst was developed by impregnating tungstophosphoric acid on sulfated zirconia by wet incipient method. The catalyst was characterized through Brunauer–Emmett–Teller (BET) surface area, temperature-programmed desorption of ammonia, temperature program reduction of hydrogen, Fourier transmission infrared spectroscopy, and thermogravimetric analysis. The results revealed that the catalyst is crystalline in nature with surface area 190–225?m2 g?1 and acidity 0.135–0.558?mmol?g?1. Twenty-five percent conversion was obtained (as confirmed by gas chromatography) at 225°C using n-hexane as model hydrocarbon in fixed-bed microreactor. 相似文献
125.
126.
Yeh David Peh Li-Shiuan Borkar Shekhar Darringer John Agarwal Anant Hwu Wen-mei 《Design & Test of Computers, IEEE》2008,25(3):272-278
The 2007 Design Automation Conference (DAC) had a special session entitled "1000 Core Chips," which was organized by Radu Marculescu (Carnegie Mellon University) and Li-Shiuan Peh (Princeton University). This session examined some of the ramifications of multicore chip design from four perspectives: technology, architecture, programming, and design automation. In this roundtable, held immediately following the conference session, the presenters expounded on the future of multicore chips with respect to education, programming languages, operating systems, and design automation. 相似文献
127.
Recent reports on highly efficient photoelectrochemical solar cells withn-type WSe2 have prompted us to grown-type single crystals of WSe2 using a chemical vapour transport method. Different transporting agents have been used. It is seen that SeCl4 transporter leads to very large single crystals ofp-type WSe2, whereas the same transporting agent with excess amount of Se leads ton-type single crystals. PEC solar cells fabricated withp-type andn-type crystals thus grown have been reported and the results discussed. 相似文献
128.
S K Agarwal M Bal G D Sharda Mahavir Singh K K Laroia 《Bulletin of Materials Science》1986,8(3):297-305
Doped and undoped polycrystalline silicon films were grown byapcvd and thermal evaporation techniques. The effect of growth and annealing conditions on the crystalline nature of the films
and their properties were studied by electrical, optical, x-ray diffraction andsem techniques. Metal silicides such as TiSi2 and PtSi2 were prepared by co-evaporation technique over polysilicon layers to study their suitability in microelectronic applications.
Some of the properties of polysilicon and silicides are discussed. 相似文献
129.
Many accounting and finance problems require ordinal multi-state classification decisions, (e.g., control risk, bond rating, financial distress, etc.), yet few decision support systems are available to aid decision makers in such tasks. In this study, we develop a Neural Network based decision support system (NN-DSS) to classify firms in four ordinal states of financial condition namely healthy, dividend reduction, debt default and bankrupt. The classification results of the NN-DSS model are compared with those of a Naïve model, a Multiple Discriminant Analysis (MDA) model, and an Ordinal Logistic Regression (OLGR) model. Four different evaluation criteria are used to compare the models, namely, simple classification accuracy, distance-weighted classification accuracy, expected cost of misclassification (ECM) and ranked probability score. Our study shows that NN-DSS models perform significantly better than the Naïve, MDA, and OLGR models on the ECM criteria, and provide better results than MDA and OLGR on other criteria, although not always significantly better. The effect of the proportion of firms of each state in the training set is also studied. A balanced training set leads to more uniform (less skewed) classification across all four states, whereas an unbalanced training set biases the classification results in favor of the state with the largest number of observations. 相似文献
130.
A serial interfacing scheme in which several embedded memories share the built-in, self-test circuit is presented. For external testing, this approach requires only two serial pins for access to the data path. There is considerable savings in routing area, and fewer external pins are needed to test random-access memories with wide words, such as those in application-specific integrated circuits for telecommunications. Even though the method uses serial access to the memory, a test pattern is applied every clock cycle because the memory itself shifts the test data. The method has been adapted to four common algorithms. In implementations of built-in self-test circuitry on several product chips, the area overhead was found to be acceptable 相似文献