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41.
Clothing plays an important role in maintaining thermal equilibrium between a human body and the ambient environment by serving as a medium for heat, moisture vapour and liquid moisture transfer. The ability of fabric to maintain this equilibrium is related to thermo-physiological comfort. Plating is an innovative knitted fabric production technique to obtain bi-layered fabrics. An attempt has been made to engineer plated knit structures with such a combination of fibre cross section in the back (inner/next to skin) and the yarn type in the face (outer) layer, so that a rapid liquid transfer from back layer by wicking and quick liquid absorption and evaporation by the face layer can be achieved. Plated fabrics using the combination of triangular polyester fibre in the back and carded cotton yarn in the face layer showed the higher thermal resistance, higher absorbent capacity and would be warmer to the initial touch. However, the combination of combed cotton yarn with triangular polyester fibre resulted in fabrics with the higher air permeability, moisture vapour transmission rate and transplanar wicking.  相似文献   
42.
Advanced technology used for arithmetic computing application, comprises greater number of approximate multipliers and approximate adders. Truncation and Rounding-based Scalable Approximate Multiplier (TRSAM) distinguish a variety of modes based on height (h) and truncation (t) as TRSAM (h, t) in the architecture. This TRSAM operation produces higher absolute error in Least Significant Bit (LSB) data shift unit. A new scalable approximate multiplier approach that uses truncation and rounding TRSAM (3, 7) is proposed to increase the multiplier accuracy. With the help of foremost one bit architecture, the proposed scalable approximate multiplier approach reduces the partial products. The proposed approximate TRSAM multiplier architecture gives better results in terms of area, delay, and power. The accuracy of 95.2% and the energy utilization of 24.6 nJ is observed in the proposed multiplier design. The proposed approach shows 0.11%, 0.23%, and 0.24% less Mean Absolute Relative Error (MARE) when compared with the existing approach for the input of 8-bit, 16-bit, and 32-bit respectively. It also shows 0.13%, 0.19%, and 0.2% less Variance of Absolute Relative Error (VARE) when compared with the existing approach for the input of 8-bit, 16-bit, and 32-bit respectively. The proposed approach is implemented with Field-Programmable Gate Array (FPGA) and shows the delay of 3.640, 6.481, 12.505, 22.572, and 36.893 ns for the input of 8-bit, 16-bit, 32-bit, 64-bit, and 128-bit respectively. The proposed approach is applied in digital filters design which shows the Peak-Signal-to-Noise Ratio (PSNR) of 25.05 dB and Structural Similarity Index Measure (SSIM) of 0.98 with 393 pJ energy consumptions when used in image application. The proposed approach is simulated with Xilinx and MATLAB and implemented with FPGA.  相似文献   
43.
Key points in the formation of liquid crystalline (LC) dispersions of graphene oxide (GO) and their processability via wet‐spinning to produce long lengths of micrometer‐dimensional fibers and yarns are addressed. Based on rheological and polarized optical microscopy investigations, a rational relation between GO sheet size and polydispersity, concentration, liquid crystallinity, and spinnability is proposed, leading to an understanding of lyotropic LC behavior and fiber spinnability. The knowledge gained from the straightforward formulation of LC GO “inks” in a range of processable concentrations enables the spinning of continuous conducting, strong, and robust fibers at concentrations as low as 0.075 wt%, eliminating the need for relatively concentrated spinning dope dispersions. The dilute LC GO dispersion is proven to be suitable for fiber spinning using a number of coagulation strategies, including non‐solvent precipitation, dispersion destabilization, ionic cross‐linking, and polyelectrolyte complexation. One‐step continuous spinning of graphene fibers and yarns is introduced for the first time by in situ spinning of LC GO in basic coagulation baths (i.e., NaOH or KOH), eliminating the need for post‐treatment processes. The thermal conductivity of these graphene fibers is found to be much higher than polycrystalline graphite and other types of 3D carbon based materials.  相似文献   
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The purpose of this study was to determine whether a relationship existed between MIB-1 labeling index (LI) percentages and survival in patients with grade II astrocytomas. From archival paraffin-embedded surgical specimens of 50 patients of the University of Michigan Medical Center with World Health Organization grade II astrocytomas, 22 patients had a Ki-67 LI of less than or equal to 2.0; and 28 patients had a MIB-1 LI of more than 2.0. Over a median follow-up interval of 10 years, ranging up to 16 years, 23% (n = 5) died of tumor in the first group while 82% (n = 23) died in the second group, a distinct difference in survival between these groups. Univariate analysis showed that a high MIB-1 predicted shorter survival (p < 0.0001), and that increased age was associated with shorter survival (p = 0.007). Gender, tumor location and radiotherapy had no significant association with survival. When adjusting for these (excluding tumor location) in the Cox proportional hazards model simultaneously, MIB-1 and age were independently prognostic. The hazard ratios were 1.301 per 1% MIB-1 LI (p = 0.0001), and 1.045 per year of age (p = 0.0028). From other studies, we know that histopathologic grade and age predict survival for glioma patients. However, even within grade II astrocytomas there is still a wide heterogeneity in how long a patient survives. We conclude that among grade II astrocytomas older patients and, independently, patients with higher MIB-1 labeling index have shorter survival.  相似文献   
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Two different orientations of an enzymatic biofuel cell (EBFC) chip, involving highly dense and three-dimensional cylindrical micro-electrodes arrays, have been studied with the finite element method. Mass transport phenomenon around the micro-electrodes of an EBFC chip inside a blood artery has been simulated. The stability of the chip to its position and blood flow pattern surrounding it are also investigated. The comparison between horizontal position (HP) and vertical position (VP) reveals that the chip can be more stable in VP rather than in HP. In VP, the diffusive flux and convective flux values are bigger compared to HP, but both these fluxes are non-uniform around all electrodes in both the positions. In addition to that in case of HP, the electrodes located at different positions on a chip receive different amount of glucose. A novel designed chip with holes through the substrate has enhanced the diffusive and convective flux in the HP of a chip and also all micro-electrodes on a chip receives similar amount of glucose uniformly throughout from the top to the bottom.  相似文献   
48.
Medium access control(MAC) protocols such as IEEE 802.11 are used in wireless networks for sharing of the wireless medium.The random nature of the protocol operation together with the inherent difficulty of monitoring in the open poses significant challenges.All nodes are expected to comply with the protocol rules.But,some nodes in order to gain greater benefits misbehave by not complying with the rules.One such selfish misbehavior is waiting for smaller back-off intervals when compared to the other node...  相似文献   
49.
Vitex negundo Linn. (VN), belonging to family Verbenaceae, is an aromatic shrub distributed throughout India. In the ayurvedic system of medicine it is used as a drug of choice to manage pain, inflammation and other related diseases. It contains many polyphenolic compounds, terpenoids, glycosidic iridoids and alkaloids. Since polyphenolic compounds have high antioxidant potential, the antioxidant potency of V. negundo was investigated by employing various established in vitro systems, such as 2,2′-azino-bis 3-ethyl benzothiazoline-6-sulfuric acid (ABTS∗+)/Lipid Peroxides (LPO)/Superoxide/Hydroxyl radical scavenging and iron ion chelation. Total antioxidant capacity was determined by the assay based on the preformed radical monocation ABTS∗+. Lipid peroxidation was assessed in terms of thiobarbituric acid reactive substances by using egg yolk homogenates as lipid rich media. Superoxide radical scavenging assay was based on the riboflavin-light-Nitro blue tetrazolium (NBT) system. Hydroxyl radical trapping potential was determined by evaluating hydroxyl radical induced deoxyribose degradation using the thiobarbituric acid method. In order to assess the metal chelation properties, hydroxyl radical induced deoxyribose degradation was evaluated in the absence of Ethylenediamine tetra acetic acid (EDTA). All the polar fractions significantly showed trapping of free radicals, and thereby inhibition of lipid peroxidation, and also chelated the iron ion. Interestingly, the hexane fraction did not show any activity against superoxides radicals and it had minimum trapping potential for other free radical (FR) species also. Thus, it may be concluded that the polar fractions of VN possess potent antioxidant properties, which may be mediated through direct trapping of the free radicals and also through metal chelation. Therefore its reported anti-inflammatory properties, could be through the down regulation of the free radical mediated pathway of inflammation.  相似文献   
50.
Pueraria tuberosa Linn. (PT), Leguminosae, is a perennial climber, growing throughout tropical parts of India. In the Ayurvedic system of medicine, it is used as a drug of choice to manage pain, inflammation and other related diseases. The antioxidant potency of P. tuberosa was investigated for the first time. Total antioxidant capacity was determined using an ABTS∗+ assay. Lipid peroxidation was assessed in terms of thiobarbituric acid-reactive substances by using egg-yolk homogenates as lipid-rich media. Superoxide radical-scavenging was measured using riboflavin-light-nitro blue tetrazolium (NBT) assay. Hydroxyl radical trapping potential was determined by evaluating hydroxyl radical induced deoxyribose degradation using thiobarbituric acid method. In order to assess the metal chelation property, hydroxyl radical induced deoxyribose degradation was evaluated in the absence of ethylenediaminetetraacetic acid. Both hexane and methanol fractions inhibited lipid peroxidation and also chelated the iron, showing potent antioxidant property.  相似文献   
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