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181.
The purpose of this study was to evaluate the effect of different surface treatment combinations on the bonding of composite resins to NiCr and titanium alloys after thermal cycling. Square-shaped specimens (10?mm x 10?mm x 2?mm) were made from NiCr and titanium alloys. The specimens were divided into 6 pretreatment groups (n?=?11): (1) machined titanium (control, no treatment); (2) CoJet sand application; (3) grinding with a diamond bur; (4) metal primer application; (5) CoJet sand?+?metal primer application; and (6) grinding with a diamond bur?+?metal primer application. The surface roughness of the mechanically treated specimens (control, grinding, CoJet sand) was evaluated. The surface morphology of both metals and elemental composition were examined with SEM and EDS. The composite resin was applied to the specimens. Shear bond strength (SBS) was tested after thermal cycling (5000 cycles, 5?°C to 55?°C). Failure modes were determined. The data were analyzed using the Shapiro-Wilk test, two-way ANOVA and post hoc Fisher’s LSD test (p?=?.05). For titanium specimens, the grinding?+?metal primer exhibited higher values than the other groups, and all groups showed higher SBS values than the control group. Combined use of CoJet sand, grinding with a diamond bur, and metal primer application would be useful for enhancing the bond strength of composite resin to titanium. The grinding of the NiCr surface with a diamond bur is the only method that could improve the bond strength of a composite resin compared to the other methods.  相似文献   
182.
Lynch syndrome (LS) is one of the most common hereditary cancer predisposition syndromes worldwide. Individuals with LS have a high risk of developing colorectal or endometrial cancer, as well as several other cancers. LS is caused by autosomal dominant pathogenic variants in one of the DNA mismatch repair (MMR) genes MLH1, MSH2, PMS2 or MSH6, and typically include truncating variants, such as frameshift, nonsense or splicing variants. However, a significant number of missense, intronic, or silent variants, or small in-frame insertions/deletions, are detected during genetic screening of the MMR genes. The clinical effects of these variants are often more difficult to predict, and a large fraction of these variants are classified as variants of uncertain significance (VUS). It is pivotal for the clinical management of LS patients to have a clear genetic diagnosis, since patients benefit widely from screening, preventive and personal therapeutic measures. Moreover, in families where a pathogenic variant is identified, testing can be offered to family members, where non-carriers can be spared frequent surveillance, while carriers can be included in cancer surveillance programs. It is therefore important to reclassify VUSs, and, in this regard, functional assays can provide insight into the effect of a variant on the protein or mRNA level. Here, we briefly describe the disorders that are related to MMR deficiency, as well as the structure and function of MSH6. Moreover, we review the functional assays that are used to examine VUS identified in MSH6 and discuss the results obtained in relation to the ACMG/AMP PS3/BS3 criterion. We also provide a compiled list of the MSH6 variants examined by these assays. Finally, we provide a future perspective on high-throughput functional analyses with specific emphasis on the MMR genes.  相似文献   
183.
Use of ozone in the food industry   总被引:2,自引:0,他引:2  
Ozone is a strong oxidant and potent disinfecting agent. Even though it is new for the US, it has been utilized in European countries for a long time. Ultraviolet radiation (188 nm wavelength) and corona discharge methods can be used to generate ozone. The bactericidal effects of ozone have been documented on a wide variety of organisms, including Gram positive and Gram negative bacteria as well as spores and vegetative cells. In this review, chemical and physical properties of ozone, its generation, and antimicrobial power of ozone with two suggested mechanisms were explained as well as many advantages of ozone use in the food industry. There are numerous application areas of ozone in the industry such as food surface hygiene, sanitation of food plant equipment, reuse of waste water, treatment and lowering biological oxygen demand (BOD) and chemical oxygen demand (COD) of food plant waste. Treating fruits and vegetables with ozone has been found to increase shelf-life of the products. Notably, when ozone is applied to food, it leaves no residues since it decomposes quickly. In this review, use of ozone in food industry was discussed.  相似文献   
184.
BACKGROUND: Intravenous gammaglobulin (i.v.IG) contains anti-idiotypic antibodies that are potent inhibitors of HLA-specific alloantibodies in vitro and in vivo. In addition, highly HLA-allosensitized patients awaiting transplantation can have HLA alloantibody levels reduced dramatically by i.v.IG infusions, and subsequent transplantation can be accomplished successfully with a crossmatch-negative, histoincompatible organ. METHODS: In this study, we investigated the possible use of i.v.IG to reduce donor-specific anti-HLA alloantibodies arising after transplantation and its efficacy in treating antibody-mediated allograft rejection (AR) episodes. We present data on 10 patients with severe allograft rejection, four of whom developed AR episodes associated with high levels of donor-specific anti-HLA alloantibodies. RESULTS: Most patients showed rapid improvements in AR episodes, with resolution noted within 2-5 days after i.v.IG infusions in all patients. i.v.IG treatment also rapidly reduced donor-specific anti-HLA alloantibody levels after i.v.IG infusion. All AR episodes were reversed. Freedom from recurrent rejection episodes was seen in 9 of 10 patients, some with up to 5 years of follow-up. Results of protein G column fractionation studies from two patients suggest that the potential mechanism by which i.v.IG induces in vivo suppression is a sequence of events leading from initial inhibition due to passive transfer of IgG to eventual active induction of an IgM or IgG blocking antibody in the recipient. CONCLUSION: I.v.IG appears to be an effective therapy to control posttransplant AR episodes in heart and kidney transplant recipients, including patients who have had no success with conventional therapies. Vascular rejection episodes associated with development of donor-specific cytotoxic antibodies appears to be particularly responsive to i.v.IG therapy.  相似文献   
185.
186.
This paper examines the effect of the gel preparation temperature (T prep) on the physical properties of the rubber-based macroporous organogels prepared by solution crosslinking in benzene at subzero temperatures. Cis-polybutadiene (CBR) and styrene-butadiene rubber (SBR) were used as the rubber components, while sulfur monochloride (S2Cl2) was the crosslinker in the gel preparation. It was shown that T prep is an extremely important parameter to adjust the porous structure and thus, the cryogel properties. The networks formed by CBR and SBR showed an aligned porous structure with an exception of honey-comb structured porous SBR cryogels prepared at ?2 °C. 101- to 102-μm sized regular pores of the networks caused by the benzene crystals act as a template during gelation, separated by 10–20 μm pore walls in thickness. They exhibit fast swelling and deswelling properties as well as reversible swelling–deswelling cycles in toluene and methanol, respectively. The ability of the organogels for the removal of petroleum products from aqueous solutions was also demonstrated using diesel and crude oil as model pollutants. In addition, the reusability of the organogels and their continuous sorption capacities were checked by repeated sorption–squeezing cycles. All the tests showed that the aligned porous organogels are suitable materials for the oil spill cleanup procedures.  相似文献   
187.
The retail sector environment is characterized by intense pressure of competition, ever-changing portfolio of products, hundreds of different products, ever-changing customer requirements and be able to stand in a mass market. When considering that the giant retailers work together with their suppliers, each independent operation is seen as a comprehensive structure, consisting of thousands of sub-processes. In short, the retail industry dynamism and work in cooperation with the competitiveness of the sector is one of a rare combination. Of course in such a sector businesses of all sizes in many aspects of creating an efficient and low cost structure is in the effort. Collaborative planning, forecasting and replenishment (CPFR) model which is a scheme integrating trading partners’ internal and external information systems is proposed to assist establishing a more effective supply chain structure in retail industry. Although CPFR can provide many benefits, there have been many failed implementations. The aim of this study is to determine the factors that will support better implementation of CPFR strategy in retail industry and analyze them using fuzzy cognitive map (FCM) approach. FCMs have proven particularly useful for solving problems in which a number of decision variable and uncontrollable variables are causality interrelated. A CPFR model made up of three sub-systems, namely information sharing, decision synchronization and incentive alignment, is proposed and “what–if” scenarios for proposed model are developed and interpreted. To our knowledge, this is the first study that uses FCMs for CPFR success factors assessment.  相似文献   
188.
Low frequency noise measurements were performed on n- and p-channel MOSFETs with TaSiN and TiN metal gates, respectively, deposited on ALD HfO2 gate dielectric. Lower normalized current noise power spectral density is reported for these devices in comparison to poly-Si/HfO2 devices and that yielded one order lower magnitude for extracted average effective dielectric trap density. In addition, the noise levels in PMOS devices were found to be higher than NMOSFETs and the dielectric trap distribution less dense in the upper mid-gap than the lower mid-gap region. The screened carrier scattering coefficient extracted from the noise measurements was approximately the same for metal and poly-Si high-k stacks but higher than that for the poly-Si SiO2 system, implying higher Coulomb scattering effects. It is believed that the elimination of dopant penetration seen in poly-Si system and low thermal budgets for metal gate deposition helped lower the noise magnitude and yielded better mobility and effective trap density values.  相似文献   
189.
This paper extends a series of recent results regarding the polynomial solvability of single and two-echelon deterministic lot sizing models. In particular, we consider a two-echelon supply chain in which production, inventory, transportation, backlogging, and subcontracting decisions are integrated. We allow for arbitrary concave cost functions and for stationary production and subcontracting capacities. We develop dynamic programming algorithms for various problems in this class that run in polynomial time in the planning horizon of the problem.  相似文献   
190.
The thermal inactivation of the highly thermo-resistant test phage (P680), was investigated in whey, whey protein concentrate (WPC) and whey cream. After a heat treatment at 90 °C for 15 min, only a 6-log reduction was obtained and the phage was still detectable in each medium. Kinetic parameters for the inactivation of the phage were calculated for temperatures ranging from 70 to 90 °C using a non-linear model. With the help of the parameters obtained, the lines of equal effects showing a 9-log inactivation of the phage were calculated. High temperature short time pasteurization was not sufficient for 9-log inactivation of phage P680 in skim milk, whey, WPC or whey cream. Temperature and time combinations ranging from 100 °C for 20 min to 140 °C for 2 s are necessary for a 9-log inactivation of P680.  相似文献   
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