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131.
132.
In mobile ad-hoc networks (MANETs), where there is no centralized authority to provide authentication, trust and reputation mechanisms are applied to maintain security by identifying trustworthy and untrustworthy nodes. However, traditional authentication mechanisms are not viable for MANETs due to the lack of infrastructure and frequent topology changes. In this paper, we propose a self-organized and localized public key authentication mechanism based on ant colony systems. Every node generates its own public-private key pair, issues certificates to neighboring nodes and provides on-demand authentication services by means of gathering certificate chains towards a target node. Pheromone concentration left by ants along the path of the certificate chains represents the trust level of a node towards other nodes. This model is able to authenticate public keys by selecting the most trustworthy certificate chains gathered by ants and can identify and exclude certificate chains with malicious nodes.  相似文献   
133.
Ozone (O3) is an emerging eco-friendly technology that has been widely used in the beverage industry due to its broad spectrum of usages, such as fermentation, microbial inactivation, Clean-in-Place (CIP) systems, and postharvest treatment. Wine is among the most financially profitable sectors of the beverage industry. Ozone technology as an alternative approach to conventional methods to inhibit microbes in wine processing and wineries has attracted researchers' attention as this emerging technology will probably play important roles in wineries in the future. This review discusses the prospective applications of ozone in winemaking and wineries and elaborates on ozone's antimicrobial effects on the control of the broad spectrum of microorganisms during wine processing. Also, this paper provides discussions on its effects of O3 on wine quality and the benefits this emerging technology can bring to wineries. Ozone treatments can improve yeast fermentation by impacting the yeast ecology of postharvested wine grapes, mainly by affecting apiculate yeasts and adjusting the population of undesirable yeasts, such as Brettanomyces spp., during the fermentation process. Furthermore, ozone treatment may enhance wine's anthocyanin concentration, physicochemical properties, color, pH, oxidative stability, and concentration of pleasant volatile compounds and esters. This article presents important information to have a better understanding of the impact of ozone treatment on different stages of wine preparation.  相似文献   
134.
The goal of this study was to investigate the effect of extrusion-forced structural changes on the extent of functional and biochemical changes of three selected protein sources that are predominantly used in aquafeed, i.e., fish meal (FM), soybean meal (SBM), and distillers dried grains with solubles (DDGS). The samples were individually extruded in a single-screw extruder using a factorial design with replicated central composite points at a temperature of 80, 110, and 140 °C; screw speed of 80, 150, and 220 rpm; and moisture content of 150, 225, and 300 (g/kg). Extrusion temperature and feed moisture significantly affected the nitrogen solubility in water (NSI), sodium dodecyl sulfate, and 2-mercaptoethanol solvents. Screw speed had only a minor effect on this value (P?<?0.05). Solubility results indicated that the contribution of hydrophobic and ionic interactions were more significant than that of the disulfide bonds, particularly for FM and SBM extrudates. For all extrudates, the highest peak viscosity was observed at the highest temperature and lowest screw speed. Extrusion processing led to considerable increase in T g of 79 % and 67 % for the DDGS and SBM samples, and a reduction of 19 % for the FM sample, respectively. Extrusion processing increased relative protein digestibility (RPD) of the SBM extrudates the most, followed by those of DDGS and FM. Overall, the severity of the extrusion conditions adversely affected available lysine content (AL) and L* color score, but relatively increased RPD of the extrudates. SBM extrudates had the lowest reduction in AL. Despite the decrease in AL, the results for both plant-based protein extrudates were comparable in quality to those of FM. The outputs of this study provide viable information for feed formulator and feed technologist in feed and food industries.  相似文献   
135.
Lycopene, a precursor of β‐carotene with well‐known antioxidant activity and powerful health properties, can be found in many natural products such as tomato (Lycopersicon esculentum), watermelon, red pepper, and papaya. Many separation methods have been reported for extracting lycopene from its sources. The inclusion complex is an effective method for extraction and purification of organic chemicals. This procedure has 2 main components: host and guest molecules. In this study, lycopene (guest) was extracted from tomato paste by ursodeoxycholic acid, the inclusive agent (host). The molecular structure of the extracted lycopene was then confirmed by 1HNMR and its purity was evaluated using high‐performance liquid chromatography and UV‐Vis spectrophotometry methods, in comparison with a standard product. The results indicated that the proposed separation method was very promising and could be used for the extraction and purification of lycopene from tomato paste.  相似文献   
136.
A short ionic-complementary peptide, EAR8-II, was employed to encapsulate the hydrophobic anticancer drug pirarubicin (THP). EAR8-II was designed to inherit advantages from two previously introduced peptides, AAP8 and EAK16-II, in their self/co-assembly. This peptide is short, simple, and inexpensive to synthesize, while possessing a low critical assembly concentration (CAC). The choice of alanine (A) residues in the peptide sequence provides moderate hydrophobic interactions, causing a minimal degree of aggregation, compared with other more hydrophobic residues. EAR8-II is an ionic-complementary peptide, similar to EAK16-II, can self/co-assemble with hydrophobic compounds such as THP, and forms a stable fibular nanostructure in aqueous solution. Physiochemical properties and cellular activities of the EAR8-II and THP complexes were evaluated and show dependency on the peptide-to-drug ratio. The complex at the peptide-to-drug mass ratio of 5:1 provides a stable solution, uniform nanostructure, and highly effective anticancer activity against various cancer cell lines. This work forms the basis for detailed studies on EAR8-II and THP formulations in vitro and in vivo, for future development of peptide-based delivery systems for hydrophobic anticancer drugs.  相似文献   
137.
Today a modern engineering environment is considered as one that emphasizes communication and involves not only many designers but also many people concerned with manufacturing, quality control, marketing, and so on working concurrently on different subparts of a more global design project. The emphasis of this paper is on the representation of product development. The current research on engineering product standards, as well as current work on databases, leads to the definition of an integrated database model for product data. However, to facilitate the integration of CAX/CAY systems and adequately support engineering and managerial activities, it is not sufficient to represent only the data between the processes, but it is also necessary to represent the processes. This paper presents an approach for simultaneous modeling of products and their development processes. This approach also provides a framework to represent the normalized product data and process data using the STEP data models.  相似文献   
138.
Electrostatic functional monomers (EFMs) play an important role in noncovalent molecular imprinting due to their formed complexes with the complementary segment(s) of the template molecule. In this work using UV difference spectroscopy, interaction saturations of methacrylic‐acid and 2‐dimethyl‐amino‐ethyl‐methacrylate in complex formation with lysozyme (Lyz) surface was found to occur at molar ratios to Lyz of 400 and 100, respectively. Based on these results and the estimated free to total EFMs ratios, four sets of imprinted/nonimprinted hydrogel samples were synthesized alongside the two sets based on lysozyme surface charges and equal EFMs. Comparisons showed that the highest absorption capacity of 59 mg/g and imprinting effect of 1.58 correspond to samples with EFM/Lyz ratios at saturation and minimum free to total EFM/Lyz ratios, respectively. Minimization of free monomers is hence important in recognition of proteins by avoiding the nonspecific binding. This can have generic application for specific separation of other macromolecules. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41366.  相似文献   
139.
The aim of the current research was to determine a less hazardous, cheaper and less toxic alternative solvent for hexane for extraction of oil from different oilseeds showing equivalent oil yield and oil quality. A full factorial design with three levels of extraction temperature (80, 100 and 120 °C) and three levels of extraction time (40, 65 and 90 min) with constant solvent to seed ratio value of 4:1 was used to extract the oil. Maximum oil was recovered from canola followed by flax, mustard and camelina. The oil content of canola was found in range of 21.08–36.44, and 25.12–40.38 % for hexane and ethyl acetate, respectively. The heating values of oil extracted from all oilseeds using hexane and ethyl acetate were found in the range of 38.04–39.98 and 37.98–39.37 MJ/kg, respectively. Least viscosity was found for flax seed using hexane followed by camelina, canola and mustard as compared to ethyl acetate. Viscosity of flax oil ranged from 27.23–37.19, and 31.16–55.52 cP for hexane and ethyl acetate solvents, respectively. Considering human safety, less environmental impact, comparable oil yield and quality parameters, ethyl acetate can be a promising alternative to hexane.  相似文献   
140.
In this research, hydrothermal‐calcination route was applied to synthesize In2O3 nanoparticles for gas sensor application. Hydrothermal synthesis with duration of 5 h at 180°C resulted in In(OH)3 nanorods. Then, in the calcination step, considering controlled rate of heating and temperature, In2O3 nanoparticles with rough surfaces were obtained. In the next step, these nanoparticles were deposited by low frequency AC electrophoretic deposition between the interdigitated electrodes to fabricate gas sensor. Deposition in the frequency of 10 kHz resulted in the chained nanoparticles in the interelectrode space. At the end, gas sensitivity measurements were conducted at 150°C–300°C and revealed that fabricated sensor had fast response and recovery times to NO2 gas.  相似文献   
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