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1.
Glial cells are crucial for maintaining central nervous system (CNS) homeostasis. They actively participate in immune responses, as well as form functional barriers, such as blood-brain barrier (BBB), which restrict the entry of pathogens and inflammatory mediators into the CNS. In general, viral infections during the gestational period can alter the embryonic and fetal environment, and the related inflammatory response may affect neurodevelopment and lead to behavioral dysfunction during later stage of life, as highlighted by our group for Zika virus infection. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) induces a cytokine storm and, during pregnancy, may be related to a more severe form of the coronavirus disease-19 (COVID-19) and also to higher preterm birth rates. SARS-CoV-2 can also affect the CNS by inducing neurochemical remodeling in neural cells, which can compromise neuronal plasticity and synaptic function. However, the impact of SARS-CoV-2 infection during pregnancy on postnatal CNS, including brain development during childhood and adulthood, remains undetermined. Our group has recently highlighted the impact of COVID-19 on the expression of molecular markers associated with neuropsychiatric disorders, which are strongly related to the inflammatory response. Thus, based on these relationships, we discussed the impact of SARS-CoV-2 infection either during pregnancy or in critical periods of neurodevelopment as a risk factor for neurological consequences in the offspring later in life, focusing on the potential role of glial cells. Thus, it is important to consider future and long-term public health concerns associated with SARS-CoV-2 infection during pregnancy.  相似文献   
2.
Botrytis cinerea (Pers.: Fr), the causal agent of botrytis bunch rot, is an important disease of grapevines worldwide, with canopy management and the prophylactic use of fungicides being the most common control methods. The latter has resulted in fungicide resistance and is increasingly raising concerns regarding residues in wine and effects on human and environmental health. Research-led alternatives to this practice are beginning to emerge, including a range of biotic and abiotic treatments that induce vine resistance to B. cinerea and inundative applications of biological control agents such as Trichoderma, Bacillus, Ulocladium and Streptomyces species. Also, habitat manipulation techniques that aim to improve the effectiveness of naturally occurring biological control are being developed using mulches brought into the vineyard, as well as mulched cover crops. These can accelerate decomposition of botrytis mycelium and sclerotia on the vineyard floor in winter. The challenges of these different techniques and the prospects for habitat manipulation for this fungal disease are discussed. Extensive tables on synthetic fungicides, biofungicides, essential oils and plant extracts effective against B. cinerea are included.  相似文献   
3.
Liquid velocity profiles in a bubble column were measured with the aid of a hot-film anemometer. Two different types of profiles were detected that were characterized by the formation of a boundary layer at the column wall. Under slow flow conditions, the boundary layer is large and controls the liquid velocity profile, but in turbulent flow the boundary layer is very small and has no significant effect on the velocity profile. Microscopic and macroscopic balances were used to predict both the liquid velocity profile and the average liquid velocity.

The effect of the liquid velocity profile and average velocity on axial dispersion and gas-hold-up are analyzed and design procedures are recommended.  相似文献   
4.
ABSTRACT: The development and spread of Acquired Immunodeficiency Syndrome (AIDS) in American urban areas is challenging established policy making structures and patterns in a variety of ways. AIDS is forcing urban policymakers to engage in unusual efforts at large and nonincremental change while possessing relatively little understanding of the ultimate nature and course of the disease. A variety of uncertainties exist, involving the future scope and development of AIDS, current and future treatment costs, legal and administrative responsibilities, workplace concerns, education efforts, financing methods, and political effects. As a consequence, those making AIDS policy must rely upon what Jones (1984) terms ambitious decisionmaking styles. Successful control of AIDS will require decentralized policymaking centered on experimental efforts in each urban area confronted with the disease. Given the wide range of uncertainties regarding the nature of AIDS and effective policy measures, it is unlikely that a truly national AIDS policy will be established in the immediate future.  相似文献   
5.
Ten male and ten female brown trout (Salmo trutta L.) ranging in weight from about 500 to 3500 grams were caught in Lake Ontario. Opposite sides of each individual fish were randomly processed and trimmed to yield skinned or unskinned fillets. Skinning resulted in an increase in the average concentration of total mercury in the fillets of fish of either sex but the increases were not significant .
With the exception of the unskinned fillets of the male fish, the concentration of mercury in the fillets increased significantly as the weight of the fish of either sex increased. The fillets of the male fish appeared to be higher in mercury than that in the corresponding fillets of female fish of comparable weight. In all instances, the concentrations of mercury in skinned and unskinned fillets were well below the 1 ppm fresh weight action level of the U.S. Environmental Protection Agency.  相似文献   
6.
Four sets of sweet potato clones obtained by meristem tip culture were used to investigate the effect of feathery mottle virus (FMV) infection on the appearance, sensory quality and chemical composition of the storage roots. This study, encompassing four generations, indicated that FMV infection had a slight effect on carbohydrate metabolism but no effect on the polyphenoloxidase-phenol system. Flavor and texture profile analyses indicated that for one clone, FMV-infected roots were more desirable when baked than healthy roots. Considering the study as a whole, FMV infection did not appear to adversely affect sweet potato sensory properties. Clones produced from the same parent by meristem tip culture might have different compositional and sensory properties.  相似文献   
7.
In a two-year study, the flavor and texture profiles and carbohydrate composition of cured, baked‘Jewels’sweet potatoes were compared to baked, uncured‘Jewels’sweet potatoes. Curing increased the rate of production of flavor notes and only slightly influenced development of “moist” mouthfeel. Given sufficient time after harvest, baked, cured roots were indistinguishable from baked, uncured roots. Carbohydrate content was not a sensitive indicator of post-harvest treatment since no statistically significant differences were detected between cured and uncured roots.  相似文献   
8.
ORIFICE DISCHARGE COEFFICIENTS FOR POWER-LAW FLUIDS   总被引:1,自引:0,他引:1  
Orifice discharge coefficients for non-Newtonian (power-law) fluids (5, 7.5 and 10% corn starch solutions) were measured using a closed end pipe with different orifice diameters. Results indicate that orifice discharge coefficients, found to be in the range of 0 – 0.7, are a function of the orifice diameter, fluid velocity in the orifice and the fluid rheological properties (consistency coefficient and flow behavior index). They increase with the fluid velocity, tend to be constant at high velocities and decrease when the consistency coefficient of the solution is increasing. Orifice discharge coefficients are presented as a function of the generalized Reynolds number.  相似文献   
9.
Residues of the miticide, dicofol, used in orchards, as well as p,p'-DDE a metabolite of p,p'-DDT present as an impurity in dicofol, were found in each commercial apple pomace sampled at several locations in Central New York. Traces of dicofol and p,p'-DDE were found in milk when cows were experimentally fed one of the pomaces for 9 days. These compounds were also detected in the milk of cows which had been fed by a dairy farmer on a practical basis for several months. It was judged that the milk residues were too low to be of health significance to consumers.  相似文献   
10.
通过旋转试验和有限元分析介绍了工件在切削加工过程中产生的畸变情况,分析了工件的装夹方式、切削速度、切削深度和进刀量对100Cr6钢环圆度的影响。通过去应力退火释放冷加工诱发的残余应力后工件的圆度与切削参数有关。另外测试了被试验环的表面残余应力,其表面残余应力与装夹方式有关。将测量的装夹力作为计算参数输入,通过有限元分析方法测试了装夹方式对工件变形的影响。协同测量结果示出了装夹方式影响工件变形的一个主要因素,表面残余应力与工件的径向变形有关,最大的拉伸应力位于夹口位置。旋转切削试验结果表明,提高切削速度圆度会稍有增加;随着切削深度的加大,圆度呈下降趋势,尽管切削力增加了;进给量的增加会导致更高的切削力,因此圆度值也增加;常规的去应力退火可使被加工环的圆度值增加。  相似文献   
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