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1.
Climate change and rising sea levels present immediate threats to humanity. However, the global catastrophe fails to generate sufficient action. Subject to total submergence within 80 years, this study undertakes an iterative design process seeking sustainable adaptation strategies for the coastal island nation of the Maldives, specifically, Malé, its capital, which exists under a “state of alert” by order of government. Research methods include literature reviews, site analysis, mapping, and iterative design processes to develop an implementation framework strategy. Infrastructure concepts are presented as speculative images with context-specific spatial relationships and functions. Concepts do not intend to represent a conclusive prototype, rather, an ideation—a solution-based discourse among key audiences highlighting the need to act decisively and adaptively.  相似文献   
2.
Simulations of bitumen recovery using solvent‐ and water‐assisted electrical heating of oil sands are presented to evaluate the process and to study gas generation. Aquathermolysis and thermal cracking and dissolution of acid‐gases in water are included. Steam‐assisted gravity drainage (SAGD) is also simulated for comparison. Results show that gas generation negatively impacts SAGD. However, in electrical heating dissolution of gases into solvent weakens their negative impact. Results indicate that SAGD generates a larger gas volume than electrical heating. In both processes, methane is found to be the major species in the produced gas and H2S concentration can reach high values. While the effect of acid–gas solubility in water on oil recovery is not evident its effect on generated gas volume is significant. Simulation results demonstrate that electrical heating is more energy efficient than SAGD. These results find application in design of experiments and pilot and field‐scale implementation of the process. © 2017 American Institute of Chemical Engineers AIChE J, 63: 4243–4258, 2017  相似文献   
3.
Novel nanosized and microsized chitosan–Al2O3–Fe3O4 (CANF and CAMF, respectively) adsorbents were functionalized with ethylenediaminetetraacetic acid (EDTA) ligands and applied to the removal of Pb(II) ions. The prepared adsorbents were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and Brunauer–Emmett–Teller analysis, and their adsorption potentials were investigated with Pb(II) as a target metal under various experimental conditions. Our results show that the EDTA functionalization of CANF and CAMF increased their adsorption capacities about 31.5 and 38 times, respectively. The optimum dosage obtained was 1.0 g/L for both EDTA‐functionalized adsorbents, and the maximum adsorption took place at pH = 5.3. The kinetic results revealed that the adsorption obeyed the pseudo‐second‐order model and that the pore diffusion process played a key role in the adsorption kinetics. Also, the results of equilibrium isotherms indicate the good fit of the experimental data by the Langmuir isotherm model under the studied concentration and temperature ranges, and the adsorptions of Pb(II) ions from aqueous solution followed the monolayer coverage of the adsorbents. The maximum Pb(II)‐ion adsorption capacities of EDTA–CANF and EDTA–CAMF were 160 and 157 mg/g, respectively. These metal‐loaded adsorbents could be readily recovered from aqueous solution by magnetic separation and reused. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44360.  相似文献   
4.
In this study, the inhibitive effect of synthesized 2-(3-pyridyl)-3,4-dihydro-4-quinazolinone (PDQ) as a new corrosion inhibitor for mild steel in 0.1 M hydrochloric acid media is investigated employing potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and linear polarization resistance (LPR) techniques. The results show PDQ reduces anodic dissolution, retards the hydrogen evolution reaction and its adsorption obeys the Langmuir's adsorption isotherm. By increase in temperature, corrosion current density increases, however, its increase is lower in the presence of PDQ. By increase in temperature from 25 °C to 45 °C the inhibition efficiency decreases from 93% to 83% in solution containing 200 ppm inhibitor. Thermodynamic adsorption parameters show that PDQ is absorbed by a spontaneous exothermic process and its adsorption mechanism is combination of physical and chemical style.  相似文献   
5.
The clinical features and outcome of thyroid cancer in 61 pregnant women (mean age, 26.0 +/- 5.9 SD yr) and in 528 female, age-matched controls who were not pregnant (mean age, 26.3 +/- 5.9 SD yr) were compared. Median follow-up was 22.4 and 19.5 yr [P = not significant (NS)] in the two groups, respectively. The thyroid nodule was asymptomatic and discovered on routine examination more often in the pregnant women (74%) than in controls (43%, P < 0.001); other clinical and tumor features were similar in the two groups. Most of the pregnant women underwent thyroidectomy after delivery (77%) or during the second trimester of pregnancy (20%). Near-total thyroidectomy was done in 43 (73%) of the pregnant women and 265 (59%) of the controls (P = NS), and nearly the same proportion of both groups (30% and 25%, respectively) were treated with 131I postoperatively. Outcome in the pregnant women and controls, respectively, was: cancer recurrence 9 (15%) and 107 (23%, P = NS); distant recurrences 1 (2%) and 12 (3%, P = NS), and cancer deaths 0 and 6 (1.2%, P = NS). Outcomes were similar when surgery was done during or after pregnancy, despite a longer delay in treatment of the latter (1.1 +/- 1.0 vs. 16.1 +/- 19.7 months, P < 0.001). This study suggests that the prognosis of differentiated thyroid cancer is the same in pregnant women and nonpregnant women of the same age, and that the diagnosis and treatment of thyroid cancer occurring during pregnancy can be delayed until after delivery in most patients.  相似文献   
6.
A Monte-Carlo reliability simulator for integrated circuits (IC) that incorporates the effects of process flaws, material properties, the mask layout, and use conditions is presented. The mask layout is decomposed into distinct objects, such as contiguous metal runs, vias, contacts, and gate-oxides, for which user-defined distributions are used for determining the failure probability. These distributions are represented by a mixture of defect-related and wearout-related distributions. The failure distributions for nets (sets of interconnected layout objects) are obtained by combining the distributions of their component objects. System reliability is obtained by applying control variate sampling to the logic network which is comprised of all nets. The effects of k-out-of-n substructures within the reliability network are accounted for. The methodology is illustrated by the effect of particulate-induced defects on metal runs and vias in a simple test circuit. The results qualitatively verify the methodology and show that predictions which incorporate failures due to process flaws are appreciably more pessimistic than those obtained from current practice  相似文献   
7.
BACKGROUND: Three groups of amino acids were previously characterized based on their ability to be assimilated as carbon source by Penicillium camembertii. To describe the diauxic growth recorded on glucose and amino acids from the second group, such as arginine, an unstructured model was previously developed, based on the sequential consumption of both carbon substrates, glucose, followed after its exhaustion, by arginine. The model was modified to describe also the behaviour recorded during growth on other amino acids. RESULTS: The growth model involved the carbon substrate consumption (Verlhust model) and the biomass on carbon substrate yield. Glucose was therefore considered during P. camembertii growth on nitrogen source amino acids (lysine—first group); and amino acid consumption was considered during growth on carbon source amino acids (glutamate—third group), with glucose being dissimilated only for energy supply. The excess nitrogen from amino acids was released as ammonium; the linking of this production to growth was found to increase with the ability of the amino acid to be assimilated as carbon source by P. camembertii. CONCLUSION: The various metabolic behaviours recorded during P. camembertii growth on amino acids, in the presence of a primary carbon source such as glucose, were proved to be satisfactorily described by the model, showing the robustness of the model. Copyright © 2007 Society of Chemical Industry  相似文献   
8.
Five newborn infants who developed subaponeurotic haemorrhage are described. Three infants were delivered by vacuum extraction, and 3 infants died. The importance of early diagnosis and prompt treatment is emphasized.  相似文献   
9.
Forty-five patients who underwent a 14 by 4 inch jejunoileal bypass for morbid obesity were studied before the operation and at periodic intervals after operation to determine the complications and changes in body composition resulting from this procedure. Body composition studies were determined using 3H2O and 42K. Rapid weight loss occurred in the first 3 months, with a mean loss of 30 percent of excess weight. This weight loss was accompanied by a decrease in exchangeable potassium (Ke) and total body water (TBW) during this interval by 14 and 10 percent, respectively. Although most patients continued to lose excess weight Ke and TBW stabilized at the end of the first year and returned to preoperative values in six patients at the end of 24 months. Analysis of the ratios of body cell mass and total body water to weight shows an improvement of body composition 12 months after operation. Body composition studies permit a quantitative assessment of the nutritional status in patients undergoing jejunoileal bypass. In spite of significant complications (23 percent), surgery for morbid obesity appears to satisfy the objective of allowing desirable loss of fat with relative sparing of muscle and other supporting tissues.  相似文献   
10.
Regarding the increasing number of cancer patients, the global burden of this disease is continuing to grow. Despite a considerable improvement in the diagnosis and treatment of various types of cancer, new diagnosis and treatment strategies are required. Nanotechnology, as an interesting and advanced field in medicine, is aimed to further advance both cancer diagnosis and treatment. Gold nanocages (AuNCs), with hollow interiors and porous walls, have received a great deal of interest in various biomedical applications such as diagnosis, imaging, drug delivery, and hyperthermia therapy due to their special physicochemical characteristics including the porous structure and surface functionalization as well as optical and photothermal properties. This review is focused on recent developments in therapeutic and diagnostic and applications of AuNCs with an emphasis on their theranostic applications in cancer diseases.  相似文献   
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