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排序方式: 共有1584条查询结果,搜索用时 15 毫秒
981.
982.
Luigi Mea Marco Sorrentino Gianfranco Rizzo Alena Trifirò Filippo Bedogni Alessio Bonifazi 《Energy Efficiency》2017,10(2):419-440
The paper presents and discusses the versatility of a first principle based model aimed at performing extensive energy scenario analyses for single telecommunication (TLC) equipment rooms. Such a modeling approach is currently under implementation on an intranet platform specifically developed to perform real-time monitoring and diagnosis, as well as offline optimization analyses based on real data acquired on the field. Specifically in this work, a model of room thermal dynamics previously developed by the authors was upgraded, in such a way as to enable its extension to any TLC room, thus also being versatile for application in different room typology and in all possible climatic locations as well. Through the model, specific energy management strategies were tested and extensively analyzed by exploring a large number of control parameters ranges. The model was also coupled to a sub-model enabling the simulation of air handling unit operated in cold ventilation, thus allowing assessing the effect of including such a low-cost operating mode, whose main features are detailed in a specific section. The performed simulations not only clearly indicate the high accuracy granted by the model in all analyzed rooms, but also demonstrate the great potential offered by well-constructed model-based optimization analyses to single out the best control parameters to be applied on a given TLC room. 相似文献
983.
Warm temperature spikes represent one of the main spoilage causes of perishable good-stuffs. The development of packaging materials with thermal buffering properties represents a powerful solution to address the problems arising from an uncontrollable interruption during cold-chain logistic.Here, we propose the use of phase change material (PCM) composites for the design of cold storage packaging. Two different concentrations (25 and 50% w/w) of commercially available micro-encapsulated PCM were homogeneously dispersed in paper matrix via conventional negative filtration techniques. The possibility of obtaining composites with different latent heats in the 4-10 °C range has been demonstrated via differential scanning calorimetry measurements. Heat transmission tests, simulating the heating processes typical of the removal from a cold room, were performed on a suitable multilayer configuration. The obtained materials show the ability to maintain the inner temperature for a duration up to 10-fold longer in time, when compared to a similar cellulose material with a thickness of 2 cm. Experimental results have been numerically assessed by considering the material thermal parameters as homogeneous.Both experimental and computational approaches here discussed offer an easy way for the design of micro-encapsulated PCM-cellulose composite as building blocks in cold storage packaging design. 相似文献
984.
Angela Sara Cacciapuoti Francesco Calabrese Marcello Caleffi Giusy Di Lorenzo Luigi Paura 《Ad hoc Networks》2012,10(8):1520-1531
In the last 10 years, new paradigms for wireless networks based on human mobility have gained the attention of the research community. These paradigms, usually referred to as Pocket Switched Networks or Delay Tolerant Networks, jointly exploit human mobility and store-and-forward communications to improve the connectivity in sparse or isolated networks. Clearly, understanding the human mobility patterns is a key challenge for the design of routing protocols based on such paradigms. To this aim, we anonymously collected the positions of almost two thousand mobile phone users, spread over a metropolitan area greater than 200 km2 for roughly one month. Then, with a multi-disciplinary approach, we estimated the mobility patterns from the collected data and, assuming Wi-Fi connectivity, we inferred the contact events among the devices to evaluate the connectivity properties of a human mobility-enabled wireless network. In a nutshell, the contribution of the paper is threefold: (i) it confirms some of the results obtained in smaller environments, such as the power-law distribution for contact and inter-contact times, allowing us to estimate the distribution parameters with high statistical significance; (ii) it addresses the feasibility of the transmission opportunities provided by human mobility to build a city-wide connected network for different forwarding strategies classes; (iii) it shows uncovered characteristics of the connectivity properties of human mobility, such as the presence of the small world phenomenon in wide-scale experiments. 相似文献
985.
986.
987.
Marian Vincenzi Susan Costantini Stefania Scala Diego Tesauro Antonella Accardo Marilisa Leone Giovanni Colonna Jean Guillon Luigi Portella Anna Maria Trotta Luisa Ronga Filomena Rossi 《International journal of molecular sciences》2015,16(6):12159-12173
This work reports on the design and the synthesis of two short linear peptides both containing a few amino acids with disorder propensity and an allylic ester group at the C-terminal end. Their structural properties were firstly analyzed by means of experimental techniques in solution such as CD and NMR methods that highlighted peptide flexibility. These results were further confirmed by MD simulations that demonstrated the ability of the peptides to assume conformational ensembles. They revealed a network of transient and dynamic H-bonds and interactions with water molecules. Binding assays with a well-known drug-target, i.e., the CXCR4 receptor, were also carried out in an attempt to verify their biological function and the possibility to use the assays to develop new specific targets for CXCR4. Moreover, our data indicate that these peptides represent useful tools for molecular recognition processes in which a flexible conformation is required in order to obtain an interaction with a specific target. 相似文献
988.
The UOP Merox? process is an efficient and economical catalytic process developed for the treatment of petroleum fractions to remove sulfur present as thiols or to directly convert thiols to less-objectionable disulfides. The key to this oxidation process is a metal-chelate redox catalyst which selectively catalyzes the oxidation of thiols with oxygen as the oxidant without causing undesirable oxidation of hydrocarbons. In this paper, we discuss the Merox? process and mechanisms by which the catalyst selectively oxidizes thiols. Additionally, we discuss the development of promoted thiol oxidation catalyst systems which eliminate the use of caustic media in the oxidation process. 相似文献
989.
Multidimensional gas chromatographic techniques applied to the analysis of lipids from wild‐caught and farmed marine species 下载免费PDF全文
990.
Mario Macchia Lucia Ceccarini Ilaria Molfetta Pier Luigi Cioni Guido Flamini 《International Journal of Food Science & Technology》2013,48(11):2370-2375
Saffron (Crocus sativus L.) is a spice used in the food industry in an ever increasing, partly due to consumer preference for natural products . Crocus sativus stigmas are converted into saffron spice by a dehydration treatment. The postharvest treatment of the stigmas, particularly the drying process, is critical to the quality of saffron as measured by the level of secondary metabolites. The aim of this project was to study the volatiles compounds in saffron that came from three different sites of the Maremma Grossetana (Grancia, Pari and Alberese) (Tuscan). The corms were grown both in the place of origin and in the province of Pisa. Fifteen compounds were detected, accounting from 92.3% to 97.8% of the total volatiles. The main characteristic volatile compounds of the dried stigmas saffron were safranal, isophorone, 4‐keto isophorone, γ‐pyronene, dihydrooxophorone. Differences were found in the composition of volatile compounds both based on the place of cultivation and in a function of time of dehydration. 相似文献