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71.
Shukla R Banerjee P Sharma SK Das R Deb P Prabaharan T Das B Adhikary B Verma R Shyam A 《The Review of scientific instruments》2011,82(10):106103
The experimental results of an air-core pulse transformer are presented, which is very compact (<10 Kg in weight) and is primed by a capacitor bank that is fabricated in such a way that the capacitor bank with its switch takes the shape of single-turn rectangular shaped primary of the transformer. A high voltage capacitor assembly (pulse-forming-line capacitor, PFL) of 5.1 nF is connected with the secondary of transformer. The transformer output voltage is 160 kV in its second peak appearing in less than 2 μS from the beginning of the capacitor discharge. The primary capacitor bank can be charged up to a maximum of 18 kV, with the voltage delivery of 360 kV in similar capacitive loads. 相似文献
72.
Shweta Pandey Asiya Mahtab Vijay Kumar Farhan Jalees Ahmad Anita Kamra Verma 《Drug development and industrial pharmacy》2013,39(7):1181-1192
The aim of this investigation is the management of rheumatoid arthritis (RA) by developing methotrexate-loaded calcium phosphate nanoparticles (MTX-CAP-NP) and to evaluate pharmacokinetic and pharmacodynamic behavior in adjuvant induced arthritis model. The nanoparticles were synthesized by wet precipitation method and optimized by Box-Behnken experimental design. MTX-CAP-NPs were characterized by TEM, FTIR, DSC and XRD studies. The particle size, zeta potential and entrapment efficiency of the optimized nanoparticles were found to be 204.90?±?64?nm, ?11.58?±?4.80?mV, and 88.33?±?3.74%, respectively. TEM, FTIR, DSC and XRD studies revealed that the developed nanoparticles were nearly spherical in shape and the crystalline structure of CAP-NP was not changed after MTX loading. The pharmacokinetic studies revealed that MTX-CAP-NP enhanced bioavailability of MTX by 2.6-fold when compared to marketed formulation (FOLITRAX-10). Under pharmacodynamic evaluation, arthritic assessment, radiography and histopathology studies revealed that CAP has ability to regenerate cartilage and bone therefore, together with MTX, MTX-CAP-NPs have shown significant reduction in disease progression. The overall work demonstrated that the developed nanodelivery system was well tolerated and more effective than the marketed formulation. 相似文献
73.
P K Khare S K Paliwal R Kuraria H L Vishwakarma Ashish Verma S K Jain 《Bulletin of Materials Science》1998,21(2):139-147
A detailed study of electrical conduction mechanism in bimetallized ferrocene-doped polyvinyl pyrrolidone films was carried
out. The measurements were carried out on films of about 20 μm thick, in the field range of (2.0–8.0) x 104 V/cm at temperatures ranging from 363 to 423 K. An investigation of the effect of impurity such as ferrocene in the polymer
matrix was undertaken. Lowering of activation energy and increase in current due to doping were observed. The results showed
that the charge carriers were generated by field-assisted lowering of coulombic barriers at the traps and were conducted through
the bulk of the material by a hopping process between the localized states by a Jonscher-Ansari modified Poole-Frenkel mechanism.
The dependence of current and activation energy on the ferrocene concentration is explained on the basis of charge transfer
type of interaction between dopant and polymeric material. 相似文献
74.
R. Vignesh Babu Kunwar Avanish Verma M. Charan S. Kanagaraj 《Advanced Powder Technology》2018,29(10):2356-2367
Copper (Cu) gained its importance in several applications due to its attractive thermal characteristics. However, its applications are limited, wherever high strength and high thermal conductivity are desirable. Thus, an attempt was made to develop Cu/CNT composites having the improved mechanical and thermal properties. Initially, Cu/CNT composite powder was synthesized through molecular level mixing technique, where the functionalized 20–40?nm and 40–60?nm diameter CNT with varying concentrations from 0.25 to 1.0?wt.% with an increment of 0.25?wt.% were used. The powder was uniaxially compacted at 800?MPa and sintered in the range of 2–8?hr at 900?°C. The best characteristics of Cu/CNT composites obtained from the present study are as follows: Relative density (RD) – 89.1%, Hardness – 61.2?±?0.58 VHN, Thermal conductivity – 343?W/mK and these characteristics obtained their maximum value at 0.25?wt.% CNT concentration and started to decrease irrespective of CNT diameter. 相似文献
75.
76.
European Journal of Wood and Wood Products - Im vorigen Teilbericht wurden Untersuchungen über Amylase von zwei Pilzen beschrieben. Der vorliegende Bericht befaßt sich mit Cellulase und... 相似文献
77.
78.
This research explored the possible application of pressurised carbon dioxide (P CO(2)), a promising non-thermal sterilisation technique, for the treatment of sewage sludge (SS) before anaerobic digestion to inactivate pathogenic microorganisms. Escherichia coli was selected as the test organism and was isolated from SS and maintained in pure culture. The growth curve of the isolated strain was determined by measuring the optical density (OD) in liquid culture medium and relating this information to the spread plate count so that a culture of known cell density could be grown for optimisation experiments. Inactivation of E. coli was enhanced by increase in pressure (1,500, 2,000 and 2,800 kPa) and treatment time (from 0.75 to 24 h). A short exposure time at high pressure was sufficient to provide a degree of inactivation which could also be achieved by longer exposure at lower pressure. Complete inactivation (8 log(10) reduction) was possible at all three pressures. scanning (SEM) and transmission (TEM) electron microscopy studies of E. coli treated with P CO(2) revealed that the cell walls were ruptured, and the cytoplasm was unevenly distributed and had lost its density, indicating the possible leakage of intracellular substances. 相似文献
79.
Sirena Soriano Kristen Curry Qi Wang Elsbeth Chow Todd J. Treangen Sonia Villapol 《International journal of molecular sciences》2022,23(9)
Traumatic brain injury (TBI) causes neuroinflammation and neurodegeneration, both of which increase the risk and accelerate the progression of Alzheimer’s disease (AD). The gut microbiome is an essential modulator of the immune system, impacting the brain. AD has been related with reduced diversity and alterations in the community composition of the gut microbiota. This study aimed to determine whether the gut microbiota from AD mice exacerbates neurological deficits after TBI in control mice. We prepared fecal microbiota transplants from 18 to 24 month old 3×Tg-AD (FMT-AD) and from healthy control (FMT-young) mice. FMTs were administered orally to young control C57BL/6 (wild-type, WT) mice after they underwent controlled cortical impact (CCI) injury, as a model of TBI. Then, we characterized the microbiota composition of the fecal samples by full-length 16S rRNA gene sequencing analysis. We collected the blood, brain, and gut tissues for protein and immunohistochemical analysis. Our results showed that FMT-AD administration stimulates a higher relative abundance of the genus Muribaculum and a decrease in Lactobacillus johnsonii compared to FMT-young in WT mice. Furthermore, WT mice exhibited larger lesion, increased activated microglia/macrophages, and reduced motor recovery after FMT-AD compared to FMT-young one day after TBI. In summary, we observed gut microbiota from AD mice to have a detrimental effect and aggravate the neuroinflammatory response and neurological outcomes after TBI in young WT mice. 相似文献
80.