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61.
62.
Adsorption characteristics of 18 proteins, with different sizes and isoelectric points, to a titanium oxide surface were studied. The adsorption isotherms were categorized based on protein type and pH: type 1, irreversible adsorption; type 2, Langmuir-type reversible adsorption; and type 3, reversible and irreversible adsorption. Most of the proteins tested were irreversibly adsorbed in the pH range of 3-8, whereas most adsorbed reversibly at pH 8.5-9.4. Protamine, with a pI value of 12, adsorbed reversibly in the pH range of 3-9. pH values that gave maximal sums of irreversibly and reversibly adsorbed proteins were in the pH range of 3-8 and tended to increase slightly with the pI value of the corresponding protein. pH values that gave maximal quantities of irreversibly adsorbed protein ranged between 4-6 and were nearly independent of pI.  相似文献   
63.
The bruchid beetles Callosobruchus chinensis (L.) and C. maculatus (F.) are destructive pests of stored mungbean (Vigna radiata (L.) Wilczek). The development of resistant mungbean varieties to manage bruchids is a major breeding objective. In the present study, we investigated the characteristics of resistance to C. chinensis and C. maculatus in two new resistant mungbean accessions V1128 and V2817, and two previously reported resistant accessions V2709 and V2802, compared to the susceptible mungbean cultivar, KPS1. Evaluation for resistance to both bruchid species using whole and decorticated seeds revealed that V1128 and V2817 were free from damage, V2709 and V2802 showed partial damage with low or moderate number of bruchids emerging from seeds, and KPS1 showed complete damage with the highest number of bruchids emerged. Comparison of the seeds harvested at seed filling, early maturity and full maturity stages revealed that the percentage of damaged seeds from resistant accessions was lower at all stages compared with KPS1. V1128 and V2817 showed complete resistance against both bruchids regardless of when their seeds were harvested, while resistance in V2709 and V2802 were most pronounced at full maturity, and KPS1 was totally damaged at all times tested. These results suggest that the chemical factor(s) conferring resistance is synthesized as early as the seed filling stage. Evaluation of resistance using artificial seeds showed that increasing the percentage of resistant seed powder adversely affected bruchid growth and development. The number of adults emerging from seeds and number of damaged seeds decreased while adult developmental period increased as the proportion of resistant seed powder increased. The weight of emerging male and female adults of C. maculatus was lighter than those from the seeds containing susceptible seed powder alone. However, C. chinensis adults were not affected by the same test. The results suggest that biochemical(s) in cotyledon tissue are responsible for the resistance and the seed coat had no protective role against the bruchids. Although all four resistant accessions evaluated are useful for mungbean breeding, V1128 and V2817 show complete resistance to both C. chinensis and C. maculatus. Thus, these two new resistant sources may be the most effective for breeding purposes.  相似文献   
64.
Because of their useful chemical and physical properties, nanomaterials are widely used around the world - for example, as additives in food and medicines - and such uses are expected to become more prevalent in the future. Therefore, collecting information about the effects of nanomaterials on metabolic enzymes is important. Here, we examined the effects of amorphous silica particles with various sizes and surface modifications on cytochrome P450 3A4 (CYP3A4) activity by means of two different in vitro assays. Silica nanoparticles with diameters of 30 and 70 nm (nSP30 and nSP70, respectively) tended to inhibit CYP3A4 activity in human liver microsomes (HLMs), but the inhibitory activity of both types of nanoparticles was decreased by carboxyl modification. In contrast, amine-modified nSP70 activated CYP3A4 activity. In HepG2 cells, nSP30 inhibited CYP3A4 activity more strongly than the larger silica particles did. Taken together, these results suggest that the size and surface characteristics of the silica particles determined their effects on CYP3A4 activity and that it may be possible to develop silica particles that do not have undesirable effects on metabolic enzymes by altering their size and surface characteristics.  相似文献   
65.
A new line equalizer system for time compression burstmode digital suhscriber loop transmission that can equalize a line with multiple bridged taps (BT's) is developed. Using the developed equalizer, up to 5 km (0.4 mmφ) line length and four BT connections can be equalized at a data rate of 80 kbits/s in each direction. The equalizer is composed of a variable gainsurd{f}step equilizer, a decision feedback automatic equalizer, and a newly developed wave difference method (WDM) timing extraction PLL. In order to fabricate the whole circuit on a single-chip LSI, most of the analog portion is organized using; switched capacitor technology. In this paper, the system design concept, circuit configuration, and results of simulations and experiiments are described.  相似文献   
66.
OBJECTIVE: To evaluate the relationship of E-cadherin (E-CD) expression to cellular DNA content and biological behavior of gastric cancer. METHODS: E-CD expression and cellular DNA content were quantitatively measured by flow cytometry and immunofluorescence methods in 80 cases of formalin-fixed, paraffin-embedded gastric cancer. Systematic pathological examinations and follow up were performed for all cases. RESULTS: E-CD expression was significantly reduced in all cases of gastric cancer, fluorescence Index (FI) of E-CD expression was 0.67 +/- 0.11 in gastric cancer, 1.0 +/- 0.07 in normal gastric mucosa (P < 0.001). The reduction of E-CD expression was also found in 2 cases of early gastric cancer. Tumors with a decrease in E-CD expression occurred significantly more frequently in undifferentiated, diffuse growth pattern Borrmann 4 type, positive lymph node (LN) metastasis and infiltrated serosa type gastric cancer, of which survival time was within 5 years (P < 0.001). E-CD expression was also reduced in gastric cancer with the number of LN metastasis above 5, metastasis to more than group 2. E-CD expression was lower in uneuploid cancer than that in diploid cancer (P < 0.01). The value of DI and PI with negative E-CD expression was significantly higher than that of positive E-CD expression (P < 0.01). CONCLUSION: Down-regulation of E-CD expression correlates with bad biological behavior and poor prognosis of gastric cancer. The reduction of E-CD expression may take place during early time of gastric cancer. Quantitative analysis of E-CD expression may have some value in evaluating the intensity of LN metastasis of gastric cancer.  相似文献   
67.
Examined the effects of life stress and support on parenting and attachment security among 53 Japanese mothers and their preschoolers who were temporarily living in the US. Mothers who had been in the US for 6 mo or less reported more life stress and less social support than did mothers who had been in the US for more than 6 mo. Measures of life stress and support were differently related to measures of parenting stress and security of attachment. When life stress was high, mothers reported more parenting stress if support was not adequate and less parenting stress if support was adequate. High support, particularly high marital support, was associated with lower levels of attachment security. Findings call for further research on family dynamics (particularly on the interplay between husband–wife and mother–child subsystems) to develop ecological models of Japanese parenting and child development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
68.
The frequency content of a mechanical shock is not confined to its fundamental frequency, so it was hypothesised that the frequency-dependence of discomfort caused by shocks with defined fundamental frequencies will differ from the frequency-dependence of sinusoidal vibration. Subjects experienced vertical vibration and vertical shocks with fundamental frequencies from 0.5 to 16 Hz and magnitudes from ±0.7 to ±9.5 ms–2. The rate of growth of discomfort with increasing magnitude of motion decreased with increasing frequency of both motions, so the frequency-dependence of discomfort varied with the magnitudes of both motions and no single frequency weighting will be ideal for all magnitudes. At the frequencies of sinusoidal vibration producing greatest discomfort (4–16 Hz), shocks produced less discomfort than vibration with same peak acceleration or unweighted vibration dose value. Frequency-weighted vibration dose values provided the best predictions of the discomfort caused by different frequencies and magnitudes of vibration and shock.

Practitioner Summary: Human responses to vibration and shock vary according to the frequency content of the motion. The ideal frequency weighting depends on the magnitude of the motion. Standardised frequency-weighted vibration dose values estimate discomfort caused by vibration and shock but for motions containing very low frequencies the filtering is not optimum.  相似文献   

69.
In order to cope with the changing health needs in the community, an holistic approach on AIDS prevention and control with particular reference to essential quality was introduced at an educational seminar at Hebei Medical University in China, 1996. We have identified three major points in the present study through learning and research process: 1. The importance of cultural norm for the unification of science and technology is identified for the community approach; 2. community care emphasising human quality provides unity in diversity for educational program; and 3. community control emphasising quality assurance demonstrates the effectiveness for program analysis from the viewpoint of human centred systems.  相似文献   
70.
Using microplates as pressure and cultivation vessels, a high-throughput method was developed for analyzing the high-pressure inactivation kinetics of microorganisms. The loss of viability from a high-pressure treatment, measured based on the growth delay during microplate cultivation, showed reproducibility with the conventional agar plate method and was applicable for the kinetics analysis.  相似文献   
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