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51.
Chlorite occurring in tremolite-chlorite schist rock of Byrapur chromite deposit of southern India has been investigated by57Fe Mössbauer spectroscopy along with XRD, IR and EPMA analyses. From XRD and EPMA results the chlorite is identified as clinochlore. The fit of Mössbauer spectrum (at room temperature) shows five symmetric doublets for iron. Based on hyperfine parameters three doublets are assigned to Fe2+ attrans andcis positions of talc layers, and Fe2+ at brucite layer. The remaining two doublets are attributed to Fe3+ attrans position and Fe3+ at tetrahedral site. The Mössbauer result suggests that the Fe3+ in octahedral sites of this chlorite was caused by oxidation after chloritization. The chlorite of Byrapur area was less oxidized compared to the chlorite of Sukinda chromite deposit of eastern India.  相似文献   
52.
This paper presents the experimental results on spruce plywood and cellulose insulation using the transient moisture transfer (TMT) facility presented in Part I [P. Talukdar, S.O. Olutmayin, O.F. Osanyintola, C.J. Simonson, An experimental data set for benchmarking 1-D, transient heat and moisture transfer models of hygroscopic building materials-Part-I: experimental facility and property data, Int. J. Heat Mass Transfer, in press, doi:10.1016/j.ijheatmasstransfer.2007.03.026] of this paper. The temperature, relative humidity and moisture accumulation distributions within both materials are presented following different and repeated step changes in air humidity and different airflow Reynolds numbers above the materials. The experimental data are compared with numerical data, numerical sensitivity studies and analytical solutions to increase the confidence in the experimental data set.  相似文献   
53.
The aim of this study was to identify the types of gallinacin genes (GALs) expressed in ovarian follicles and to determine the changes in their expression during follicular growth and in response to lipopolysaccharide (LPS). Follicles at different stages of growth were collected from laying hens (n = 5) and LPS-injected hens (n = 3). The expression of GALs in the theca and granulosa layers was examined by semi-quantitative RT-PCR. The expression of GAL-1, -2, -7, -8, -10, and -12 in the theca layer and GAL-1, - 8, -10, and -12 in the granulosa layer was identified in white and yellow follicles. The expression of these genes was not changed in the theca and granulosa layers during follicular growth except for a decrease in that of GAL-1 in theca. The expression of GAL-1, -7, and -12 in the theca layer of the third largest follicles was increased in response to LPS at a dose of 1 mg/kg body weight and this increase was induced within 3 h and maintained until 12h postinjection. Granulosa layers did not respond to LPS until 12h injection. These results show that six and four types of GALs are expressed in the theca and granulosa layers of healthy follicles respectively, and their levels do not change with follicular growth except for GAL-1 in theca. Elevated levels of GAL-1, -7, and -12 expression in theca in response to LPS suggest that the theca cells expressing these GALs function to eliminate LPS-containing bacteria.  相似文献   
54.
We have performed atomistic molecular dynamics (MD) simulations of water molecules inside narrow, open-ended carbon nanotubes placed in a bath of water molecules. The radius of the tube is such that only a single file of water molecules is allowed inside the tube. The confined water molecules are shown to be positionally ordered even at a temperature of 300 K. The calculated mean-square displacement (MSD) of the confined water molecules reveals that initially the water molecules undergo ballistic motion that crosses over to normal (Fickian) diffusion at longer times. We also develop a random-walk model in 1D for the motion of a cluster of water molecules inside the nanotube. The agreement of the MSD calculated from the MD simulation and from the 1 D random-walk model establishes the occurrence of normal diffusion of water molecules even in a tube where single-file diffusion is expected.  相似文献   
55.
Reactive oxygen species (ROS) cause oxidative stress by generating reactive aldehydes known as 4-hydroxynonenal (4-HNE). 4-HNE modifies protein via covalent adduction; however, little is known about the degradation mechanism of 4-HNE-adducted proteins. Autophagy is a dynamic process that maintains cellular homeostasis by removing damaged organelles and proteins. In this study, we determined the role of a superoxide dismutase (SOD) mimetic MnTnBuOE-2-PyP5+ (MnP, BMX-001) on rotenone-induced 4-HNE aggresome degradation in HL-1 cardiomyocytes. A rotenone treatment (500 nM) given for 24 h demonstrated both increased ROS and 4-HNE aggresome accumulation in HL-1 cardiomyocytes. In addition, cardiomyocytes treated with rotenone displayed an increase in the autophagy marker LC3-II, as shown by immunoblotting and immunofluorescence. A pre-treatment with MnP (20 µM) for 24 h attenuated rotenone-induced ROS formation. An MnP pre-treatment showed decreased 4-HNE aggresomes and LC3-II formation. A rotenone-induced increase in autophagosomes was attenuated by a pre-treatment with MnP, as shown by fluorescent-tagged LC3 (tfLC3). Rotenone increased tubulin hyperacetylation through the ROS-mediated pathway, which was attenuated by MnP. The disruption of autophagy caused HL-1 cell death because a 3-methyladenine inhibitor of autophagosomes caused reduced cell death. Yet, rapamycin, an inducer of autophagy, increased cell death. These results indicated that a pre-treatment with MnP decreased rotenone-induced 4-HNE aggresomes by enhancing the degradation process.  相似文献   
56.
This study reports on the effect of the addition of Glycine to Hank's solution on the in-vitro corrosion behavior of AZ31 magnesium (Mg) alloy at 37 ℃ and a pH of 7.4 studied by using potentiodynamic polarization (PDP),hydrogen collecting techniques and electrochemical impedance spectroscopy (EIS) in combination with surface characterization techniques such as optical microscopy (OM),scanning electron microscopy(SEM),energy dispersive spectroscopy (EDS),X-ray diffraction (XRD) and X-ray photoelectron spectroscopy analysis (XPS).The results reveal that adsorption of glycine initially subdues the dissolution ofAZ31 Mg alloy while in long run it enhances the dissolution of the alloy due to the commencement of the chelation effect ofglycine with Ca2+ released from hydroxyapatite.The chelation ofglycine with Ca2+induces the formation of cracks in the surface film which further promotes the dissolution ofAZ31 Mg alloy thereby forming a porous corrosion products layer on the surface of the alloy.As a result,both the continuous dissolution of AZ31 magnesium alloy and the hydrogen evolution rate (HER) are enhanced with increasing the immersion time in Hank's solution.  相似文献   
57.
Advances in spectroscopy now enable researchers to obtain information about chemical and physical components in food or biological materials at the molecular level. Various spectroscopic techniques (e.g., atomic absorption spectroscopy, Raman and Fourier-transform infrared spectroscopy, near infrared spectroscopy, nuclear magnetic resonance spectroscopy, mass spectroscopy, X-ray fluorescence spectroscopy, ultra-violet spectroscopy) have been used to study structure-function relationships in foods (both liquid and solid) to improve overall food quality, safety and sensory characteristics; to investigate fungal infections in plant materials (e.g., fruits, seeds); or to study mobility of different chemical components in food materials. Processing, analyzing, and displaying these data can often be difficult, time-consuming, and problem-specific. Chemometrics is well established for calibrating the spectral data to predict concentrations of constituents of interest. Similarly, proteomics deals with the structure-function relationship of proteins. Since most of the food processing industries are becoming increasingly automated, there is a need to understand how the spectroscopic data can be used for automation. In this paper, we have provided basic working principles of the above mentioned spectroscopic techniques, examples of the use of spectral data in food processing, methods of analysis of spectral data and their integration in the automation process. Meeting presentation: Food Processing Automation Conference, Providence, RI, 28–29 June 2008. ASABE Publication Number 701P0508 cd.  相似文献   
58.
Maiti PK  Bagchi B 《Nano letters》2006,6(11):2478-2485
We study sequence-dependent complexation between oligonucleotides (single-strand DNA) and various generation ethylene diamine (EDA) cored poly amido amide (PAMAM) dendrimers through atomistic molecular dynamics simulations accompanied by free energy calculations and inherent structure determination. Simulations reveal formation of a stable complex and provide a detailed molecular level understanding of the structure and dynamics of such a complexation. The reaction free energy surface in the initial stage is found to be funnel-like, with a significant barrier arising in the late stage due to the occurrence of misfolded states of DNA. Complexation shows surprisingly strong sensitivity to the ssDNA sequence, which is found to arise from a competition between enthalpic versus entropic rigidity of ssDNA.  相似文献   
59.
A zinc–air fuel cell (ZAFC), which generates electricity by the reaction between oxygen and zinc pallets in a liquid alkaline electrolyte, is a potential candidate for an alternative energy generator. It is efficient, completely renewable, and cheap in fabrication because precious metal catalysts are not necessary. In addition, it is environmentally benign because of producing solely recyclable zinc oxide without gas emission. It is applicable to portable, mobile, stationary, and military purposes. In spite of its high potential as an alternative power source, it is yet in a preliminary stage of commercialization because of a few uncertainties remained. This paper reviews the present status of the ZAFC technology and the problems to be overcome for further advancement toward the potential next-generation alternative energy.  相似文献   
60.
A novel wavy‐shaped thin‐film‐transistor (TFT) architecture, capable of achieving 70% higher drive current per unit chip area when compared with planar conventional TFT architectures, is reported for flexible display application. The transistor, due to its atypical architecture, does not alter the turn‐on voltage or the OFF current values, leading to higher performance without compromising static power consumption. The concept behind this architecture is expanding the transistor's width vertically through grooved trenches in a structural layer deposited on a flexible substrate. Operation of zinc oxide (ZnO)‐based TFTs is shown down to a bending radius of 5 mm with no degradation in the electrical performance or cracks in the gate stack. Finally, flexible low‐power LEDs driven by the respective currents of the novel wavy, and conventional coplanar architectures are demonstrated, where the novel architecture is able to drive the LED at 2 × the output power, 3 versus 1.5 mW, which demonstrates the potential use for ultrahigh resolution displays in an area efficient manner.  相似文献   
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