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81.
Packaging must have a good commercial appearance and is generally obtained by ink transferred to its substrate. It is important that the ink used in packaging printing is produced from environmentally friendly and sustainable raw materials as well as being suitable for the printing system. The increasing demand in the field of printed packaging and the scarcity of resources to meet this demand have accelerated the search for new sources for inks. For this purpose, inks produced in the laboratory using a modified cellulose-based binder, a commercial acrylic resin and a commercial soybean protein were compared with a commercial ink. As a result of the study, it was determined that the printability properties of the ink obtained by using the modified cellulose-based binder were better than the ink obtained with commercial soybean protein. It was determined that it showed printability properties close to the ink produced with commercial acrylic binders. By using modified cellulose-based water-based flexographic ink instead of other commonly used binders, more environmentally friendly sustainable inks can be produced.  相似文献   
82.
83.
The analytic representation of the exact coagulation kernel for combined Brownian motion and gravitational settling entails an infinite sum of ratios of modified Bessel functions. Heretofore, the evaluation of this sum has been limited to relatively small arguments due to computational difficulties, hindering the numerical solution of the general dynamic equation in computational aerosol transport simulations. An approximation and an asymptotic extension have been available, but their accuracy for large arguments has not been established, and they have been shown to lead to numerical diffusion and oscillation. Using multiple-precision arithmetic, exact values for the kernel are presented in this paper for large arguments, and it is shown that both the asymptotic and approximating formulae provide a poor fit in the range of practical interest. Based on the results, the asymptotic formula is rectified and it is shown that the approximation is no longer needed. Practical formulae are given to facilitate rapid numerical evaluation of the exact kernel for all arguments.  相似文献   
84.
Forty-nine primiparous and 44 multiparous lactating Holstein cows were used to study the effect of five dietary forage: grain ratios on blood constituents. Blood samples were collected in wk 2, 3, 4, 6, 8, 12, and 16 of lactation and were analyzed for glucose, urea, beta-hydroxybutyrate, and FFA. Increasing the percentage of forage in the diet decreased blood glucose concentration. Glucose levels were low at the beginning of lactation and increased as DMI increased. Increasing percentage of forage in the diet did not affect blood urea concentration. Increasing forage in the diet from 38.2 to 98.2% increased beta-hydroxybutyrate concentrations threefold during the first 4 wk of lactation in both primiparous and multiparous cows. The concentration of plasma FFA was higher in all the treatments at the beginning of lactation and decreased as lactation advanced. Dietary forage:grain ratio did not affect plasma FFA.  相似文献   
85.
Red and white guavas were treated with wax emulsion or irradiation (0.25-2.0 kGy) and kept for 12 days at room temperature. Initiation of rot attack occurred after 3 days which increased significantly during further storage. In the waxed fruits rottage, weight loss and vitamin loss were significantly less than controls and irradiated ones. Sensory scores decreased with storage time and they ranged 3.7-4.5, 2.1-3.9 and 2.3-2.7 in waxed, radiated and untreated controls respectively, after 12 days storage. Waxing was found to increase the. shelf life of this fruit for 3-4 d while irradiation exhibited no beneficial effects.  相似文献   
86.
A continuous increase in the greenhouse gases concentration due to combustion of fossil fuels for energy generation in the recent decades has sparked interest among the researchers to find a quick solution to this problem. One viable solution is to use hydrogen as a clean and effective source of energy. In this paper, an extensive review has been made on the effectiveness of metallic catalyst in hydrocarbon reforming for COX free hydrogen production via different techniques. Among all metallic catalyst, Ni-based materials impregnated with various transition metals as promoters exhibited prolonged stability, high methane conversions, better thermal resistance and improved coke resistance. This review also assesses the effect of reaction temperature, gas hour space velocity and metal loading on the sustainability of thermocatalytic decomposition TCD of methane. The practice of co-feeding of methane with other hydrocarbons specifically ethylene, propylene, hydrogen sulphide, and ethanol are classified in this paper with the detailed overview of TCD reaction kinetics over an empirical model based on power law that has been presented. In addition, it is also expected that the outlook of TCD of methane for green hydrogen production will provide researchers with an excellent platform to the future direction of the process over Ni-based catalysts.  相似文献   
87.
Microcalcifications are an early mammographic sign of breast cancer and a target for stereotactic breast needle biopsy. We developed Raman spectroscopy decision algorithms to detect breast microcalcifications, based on fit coefficients (FC) derived by modeling tissue Raman spectra as a linear combination of the Raman spectra of 9 chemical and morphologic components of breast tissue. However, little or no information is available on the precision of such measurements and its effect on the ability of Raman spectroscopy to make predictions for breast microcalcification detection. Here we report the precision, that is, the closeness of agreement between replicate Raman spectral measurements - and the model FC derived from them - obtained ex vivo from fresh breast biopsies from patients undergoing stereotactic breast needle biopsy, using a compact clinical Raman system. The coefficients of variation of the model FC averaged 0.03 for normal breast tissue sites, 0.12 for breast lesions without, and 0.22 for breast lesions with microcalcifications. Imprecision in the FC resulted in diagnostic discordance among replicates only for line-sitters, that is, tissue sites with FC values near the decision line or plane. The source of this imprecision and their implications for the use of Raman spectroscopy for guidance of stereotactic breast biopsies for microcalcifications are also discussed. In summary, we conclude that the precision of Raman spectroscopy measurements in breast tissue obtained using our compact clinical system is more than adequate to make accurate and repeatable predictions of microcalcifications in breast tissue using decision algorithms based on model FC. This provides strong evidence of the potential of Raman spectroscopy guidance of stereotactic breast needle biopsies for microcalcifications.  相似文献   
88.
Diets containing 0.31, 0.39, or 0.47% P on a DM basis were fed to 10, 14, and 13 multiparous Holstein cows, respectively, for a full lactation. Most of the cows (33) were fed similar amounts of P in the previous one or two lactations. The objective was to obtain information on bone integrity after prolonged feeding of different amounts of P. At the end of the experiment, a section (-20 cm) of the 12th rib was surgically removed. The bone was tested for strength and analyzed for ash and P content. The shear strength and the energy required to deform the bone to the point of fracture did not differ among treatments. Bone specific gravities were 1.50, 1.57, and 1.55 for the three treatments. Ash and P content of the bone, measured in wet weight, dry weight, and wet bone volume, were similar for the 0.39 and 0.47% P treatments, but tended to be lower with the 0.31% P treatment. Milk production of cows in all groups was high, averaging >11,900 kg for the 308-d lactation. Feeding P at 0.31% of dietary DM over two to three lactations appeared to decrease P concentration of bone, but the decrease was not severe enough to affect bone strength. Dietary P at 0.39% did not affect bone P content or strength. Dietary P content of 0.31% appears to be borderline deficient for cows producing >11,900 kg/308 d.  相似文献   
89.
Two experiments were conducted to determine the conjugated linoleic acid (CLA) content of milk from cows offered diets rich in linoleic and linolenic acid. In experiment 1, 36 cows were assigned to a control and five treatment groups. Cows in the control group received a diet containing 51% forage and 49% grain on a dry matter basis. In the treatment group, grain was partly replaced by either 18% raw cracked soybeans, 18% roasted cracked soybeans, 3.6% soybean oil, 2.2% linseed oil, or 4.4% linseed oil. Experimental diets were fed for 5 wk. Average CLA contents in milk fat from wk 2 through 5 were 0.39% in control and 0.37, 0.77, 2.10, 1.58, and 1.63% of total fatty acids in the raw soybean, roasted soybeans, soybean oil, 2.2% linseed oil, and 4.4% linseed oil treatments, respectively. In experiment 2, 36 cows were assigned to a control and 5 treatment groups. Cows in the control group received a diet containing 55% forage and 45% grain. In the treatment groups, grain was partly replaced by soybean oil at 0.5, 1.0, 2.0, 4.0, or by linseed oil at 1.0% of the dietary dry matter. Experimental diets were fed for 5 wk. Average CLA contents in milk fat from wk 2 through 5 were 0.50% in control and 0.75, 0.76, 1.45, 2.08, and 0.73% of total fatty acids in 0.5, 1.0, 2.0, 4.0 soybean oil and 1.0% linseed oil treatments, respectively. Diets rich in linoleic or linolenic acid can increase CLA content of milk when dietary oil is accessible to the rumen microorganisms.  相似文献   
90.
Milk production response to dietary forage:grain ratio   总被引:2,自引:0,他引:2  
Forty-four multiparous and 49 primiparous Holstein cows were assigned randomly at parturition to one of five diets differing in forage:grain ratio and studied for the entire lactation for effects of diet on milk production and milk composition, body condition, BW gain, health, and reproductive performance. Total mixed rations fed once daily consisted of alfalfa silage, high moisture ear corn, soybean meal, vitamins, and minerals. Percentages of forage in the diet (dry basis) for treatments 1 to 5 were postpartum wk 1 to 12 (38.2, 48.2, 58.2, 68.2, and 98.2); wk 13 to 26 (48.2, 58.2, 68.2, 88.2, and 98.2); and wk 27 to 44 (68.2, 78.2, 88.2, 98.2, and 98.2). Milk production (3.5% FCM in 305 d) was 8295, 8659, 7563, 6849, and 6000 kg for multiparous cows in treatments 1 to 5, respectively, and 7334, 7177, 6976, 6014, and 4750 kg for primiparous cows. Primiparous cows had decreased milk protein, BW gain, DMI and gross feed efficiency as forage increased in the diet. Multiparous cows in treatment 1 had depressed milk fat and lower DMI and gross feed efficiency compared with other treatments. Body condition scores tended to be lower as forage increased in the diet with both age groups. Increased forage in the diet did not cause any adverse effects on health and reproductive performance in either age group.  相似文献   
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