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41.
Rat heart preparations metabolized erucic acid at much slower rates than palmitic acid. This applied for activation reaction, for the conversion of acyl-CoA to acylcarnitine, and for the utilization of acyl group for oxidation. As compared to palmityl-CoA, erucyl-CoA exhibited a lower affinity for carnitine palmityltransferase (EC 2.3.1 23), the respective apparent Michaelis constants were 43 and 83 μM. Presence of erucyl-CoA or erucylcarnitine slowed the mitochondrial oxidation of palmityl groups apparently because of the slower oxidation of erucyl groups. However, presence of erucate did not inhibit the activation of palmitate. Heart mitochondria obtained from rats fed rapeseed oil (50 cal %) or corn oil diet for 3 days showed similar abilities for the coupled oxidation of various substrates and similar carnitine palmityltransferase activities. Thus a suggestion of gross mitochondrial malfunction following rapeseed oil consumption was not confirmed.  相似文献   
42.
43.
\(\hbox {La}_{0.8}\hbox {Sr}_{0.2}\hbox {MnO}_{3-\delta }\) (LSM)/8 mol% yttria-stabilized \(\hbox {ZrO}_{2}\) (YSZ) (LSM/YSZ) composite cathodes with varying composition are studied for both polarization and ohmic resistance by electrochemical impedance spectroscopy. It was found that total resistance and polarization resistance are lowest for the composite with 60 wt% of LSM (LSM60/YSZ40). However, the ohmic resistance was highest for the same composition and amounted to 60% of the total resistance value. Compositional dependence of resistances has been explained based on the variations of the triple phase boundaries and width of the \(\hbox {O}^{2-}\) ion migration path with the composition of the electrode. Based on the observed area specific ohmic resistance values for the composite cathodes, it is proposed to verify the advantages of LSM/YSZ over LSM cathode in anode-supported solid oxide fuel cell with thin electrolyte.  相似文献   
44.
With the emergence of the Internet of things (IoT), embedded systems have now changed its dimensionality and it is applied in various domains such as healthcare, home automation and mainly Industry 4.0. These Embedded IoT devices are mostly battery-driven. It has been analyzed that usage of Dynamic Random-Access Memory (DRAM) centered core memory is considered the most significant source of high energy utility in Embedded IoT devices. For achieving the low power consumption in these devices, Non-volatile memory (NVM) devices such as Parameter Random Access Memory (PRAM) and Spin-Transfer Torque Magnetic Random-Access Memory (STT-RAM) are becoming popular among main memory alternatives in embedded IoT devices because of their features such as high thickness, byte addressability, high scalability and low power intake. Additionally, Non-volatile Random-Access Memory (NVRAM) is widely adopted to save the data in the embedded IoT devices. NVM, flash memories have a limited lifetime, so it is mandatory to adopt intelligent optimization in managing the NVRAM-based embedded devices using an intelligent controller while considering the endurance issue. To address this challenge, the paper proposes a powerful, lightweight machine learning-based workload-adaptive write schemes of the NVRAM, which can increase the lifetime and reduce the energy consumption of the processors. The proposed system consists of three phases like Workload Characterization, Intelligent Compression and Memory Allocators. These phases are used for distributing the write-cycles to NVRAM, following the energy-time consumption and number of data bytes. The extensive experimentations are carried out using the IoMT (Internet of Medical things) benchmark in which the different endurance factors such as application delay, energy and write-time factors were evaluated and compared with the different existing algorithms.  相似文献   
45.
In the present study, the coagulation of the fresh and thermally treated desizing wastewater has been reported. The maximum COD reduction of fresh desizing wastewater using coagulation was observed with commercial alum at initial pH 4. This was followed by aluminum potassium sulfate (pH 4), FeCl(3) (pH 6), PAC (pH 6) and FeSO(4) (pH 4). The maximum COD reduction observed at a coagulant (commercial alum) dose of 5 kg/m(3) and pH 4 was 58% whereas the color reduction at these conditions was 85%. The results reveal that the application of coagulation on the catalytic thermal treated effluent is more effective in removing nearly 88% of COD and 96% of color at above mentioned conditions except at a coagulant dose of 1 kg/m(3). The amount of inorganic sludge generated gets drastically reduced (almost 25%) due to the reduced amount of coagulant. The COD and color of the final effluent were found to be 98.6 mg/l and 2.67 PCU, respectively, and the COD/BOD(3) ratio was 1.36. The settling rate of the slurry was found to be strongly influenced by treatment pH. The slurry obtained after treatment at pH 12 settled faster in comparison to slurry obtained at pH 4. The filterability of the treated effluent is also strongly dependent on pH. pH 12 was adjudged to be the best in giving highest filtration rate.  相似文献   
46.
D.c. electrical conductivity studies have been reported in Na2Ti3O7 in the temperature range 370–750 K. Three distinct regions have been identified in the log(T) versus 1000/T plots, the lowest temperature region being proposed to be due to electronic hopping conduction involving loose electrons of Ti3O 7 2– groups, the intermediate region to associated extrinsic ionic conduction through dilated interlayer space and the highest temperature region to modified interlayer ionic conduction, the modification being affected by loose oxygens from Ti3O 7 2– groups. The room-temperature electron paramagnetic resonance (EPR) investigations have been interpreted in terms of manganese substitution in the lattice. For a lower percentage of doping the substitution of manganese ions occur as Mn3+ at Ti4+ sites, whereas for a higher percentage of doping, Mn2+ ions predominantly occupy the interlayer Na+ sites. The dilation of interlayer space has further been proposed to occur due to a Ti4+ substitution of manganese ions.  相似文献   
47.
The effect of La3+ doping on Ca2+ sites in CaCu3Ti4O12 (CCTO) was examined. Polycrystalline samples in the chemical formula Ca(1-x)La(2/3)x Cu3Ti4O12 with x = 0, 0.5, 1 were synthesized via the conventional solid state reaction route. X-ray powder diffraction analysis confirmed the formation of the monophasic compounds and indicated the structure to be remaining cubic with a small increase in lattice parameter with increase in La3+ doping. The dielectric and impedance characteristics of Ca(1-x)La(2/3)x Cu3Ti4O12 were studied in the 100 Hz–10 MHz frequency range at various temperatures (100–475 K). A remarkable decrease in grain size from 50 μm to 3–5 μm was observed on La3+ substitution. The dielectric constant of CaCu3Ti4O12 decreased drastically on La3+ doping. The frequency and temperature responses of dielectric constant of La3+ doped samples were found to be similar to that of CaCu3Ti4O12. The effects of La3+ doping on the electrical properties of CaCu3Ti4O12 were probed using impedance spectroscopy. The conducting properties of grain decreased while that of the grain boundary increased on La3+ doping, resulting in a decrease of the internal barrier layer effect. A decrease in grain boundary capacitance and stable grain response in La3+ doped CCTO ceramics were unambiguously established by modulus spectra studies.  相似文献   
48.
The decolorization and reduction of COD of dyeing wastewater from a cotton textile mill was conducted using catalytic thermal treatment (thermolysis) accompanied with/without coagulation. Thermolysis in presence of a homogeneous copper sulphate catalyst was found to be the most effective in comparison to other catalysts (FeCl(3), FeSO(4), CuO, ZnO and PAC) used. A maximum reduction of chemical oxygen demand (COD) and color of dyeing wastewater of 66.85% and 71.4%, respectively, was observed with a catalyst concentration of 5 kg/m(3) at pH 8. Commercial alum was found most effective coagulant among various coagulants (aluminum potassium sulphate, PAC, FeCl(3) and FeSO(4)) tested during coagulation operations, resulting in 58.57% COD and 74% color reduction at pH 4 and coagulant dose of 5 kg/m(3). Coagulation of the clear fluid (supernatant) obtained after treatment by thermolysis at the conditions previously used resulted in an overall reduction of 89.91% COD and 94.4% color at pH 4 and a coagulant dose of 2 kg/m(3). The application of thermolysis followed by coagulation, thus, is the most effective treatment method in removing nearly 90% COD and 95% color at a lower dose of coagulant (2 kg/m(3)). The sludge thus produced would contain lower inorganic mass coagulant and, therefore, less amount of inorganic sludge.  相似文献   
49.
A series of Eu(III) doped MSiO3 (M = Mg, Ca, Sr and Ba) nanomaterials of high color purity were prepared using sol–gel technique at 950 °C. Samples were further reheated at 1050 and 1150 °C for 1 h in muffle furnace to study the effect of temperature on the structural aspects and optical characteristic of prepared materials. X-ray diffraction study was used to know the crystal structure of synthesized silicate phosphors. All the prepared materials existed in the single phase and dopant ion have no influence on the crystal structure of host materials. Under 395 nm excitation, photoluminescence emission spectra of silicate materials showed the characteristic red emission in 610–615 nm region due to the electric dipole (5D0 → 7F2) transition of europium(III) ion. Color coordinate values of these materials were located in the red region of Commission Internationale de I’Eclairage triangle. Fourier transform infra red spectroscopic studies were used to know the structure and bonding present in these phosphors. Transmission electron microscopic confirmed that the particle size of prepared nanomaterials exist in the nano range. The results suggested that these red emitting phosphors could be useful for generation of white-light emitting diode applications.  相似文献   
50.
Separators in supercapacitors (SCs) typically suffer from defects of low mechanical property, limited ion transport, and electrolyte wettability, and poor thermal stability, impeding the development of SCs. Herein, high-performance regenerated cellulose (RC) based separators are designed that are fabricated by effective hydrolytic etching of inorganic CaCO3 nanoparticles from a filled RC membrane. The as-prepared RC separator displays excellent comprehensive performances such as higher tensile strength (75.83 MPa) and thermal stability (200 °C), which is superior to commercial polypropylene-based separator (Celgard 2500) and sufficient to maintain their structural integrity even at temperatures in excess of 200 °C. Benefiting from its hydrophilicity, high porosity, and outstanding electrolyte uptake rate (208.5%), the RC separator exhibits rapid transport and permeability of ions, which is 2.5× higher than that of the commercial nonwoven polypropylene separator (NKK -MPF30AC-100) validated by electrochemical tests in the 1.0 m Na2SO4 electrolyte. Results show that porous RC separator with unique advantages of superior electrolyte wettability, mechanical robustness, and high thermal stability, is a promising separator for SCs with high-performance and safety.  相似文献   
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