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941.
A k-set structure is a sub-linear space data structure that supports multi-set insertion and deletion operations and returns the multi-set, provided the number of distinct items with non-zero frequency does not exceed k. This is a fundamental problem with applications in data streaming [S. Muthukrishnan, Data streams: Algorithms and applications, Foundations and Trends in Theoretical Computer Science 1 (2) (2005)], distributed systems [Y. Minsky, A. Trachtenberg, R. Zippel, Set Reconciliation with Nearly Optimal Communication Complexity, IEEE Trans. Inform. Theory 49 (9) (2003) 2213-2218; D. Starobinski, A. Trachtenberg, S. Agarwal, Efficient PDA synchronization, IEEE Trans. on Mob. Comp. 2 (1) (2003) 40-51], etc. In this paper, we present the design of a deterministic k-set structure. 相似文献
942.
Khokan Kanti Majumder Graham Hobbs Sati N. Bhattacharya 《Polymer Engineering and Science》2007,47(12):1983-1991
The molecular weight and its distribution, degree of long chain branching and cooling rate strongly influence crystallinity during processing, which in turn determines the processability and the ultimate properties of the blown film. Generally a decrease in the number of branches and molecular weight of the polymer and the cooling rate results in an increase of the crystallinity. Length of the main chain and extent of branching in low‐density polyethylene (LDPE) are also factors that affect melt rheology and film crystallinity. Long chain branched polyethylene is suitable in the blown film process due to its better melt strength for bubble stability. The objective of this article is to describe the effect of molecular properties (e.g. molecular weight and its distribution, degree of long chain branching etc) of LDPE on film crystallinity at different cooling rates of blown film extrusion. Two different grades of LDPE were selected to investigate molecular characteristics, crystallinity, and rheology. The resins were processed in a blown film extrusion pilot plant using four different cooling rates. Molecular, rheological, and crystalline properties of the resins were key parameters considered in this study. POLYM. ENG. SCI., 47:1983–1991, 2007. © 2007 Society of Plastics Engineers 相似文献
943.
Effect of a novel combined enterosorbent "Ultrasorb" on biochemical and morphologic blood parameters
SS Stavitskaia VV Kirsenko VN Karpenko NT Kartel' VI Davydov TP Petrenko NV Gerasimenko SG Korviakova 《Canadian Metallurgical Quarterly》1996,68(4):95-100
In order to estimate toxicity of a novel composition, enterosorbent "ultrasorb", its toxic properties were studied in trials on experimental animals (white rats, mice, guinea pigs). Great variety of hematolytic, biochemical and pathohistologic parameters were determined to evaluate homeostasis. As a result of toxicity trials in acute and subacute experiments as well as in embryotoxic, teratogenic and allergic tests we have concluded that enterosorbent "Ultrasorb" is absolutely harmless and can be recommended for further trials in clinics. 相似文献
944.
Halime Abakay Temel Arun Kumar Majumder 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(8):1048-1054
This study investigated the possibility of cleaning Malatya-Arguvan lignite using the flotation method. Because preliminary flotation studies suggested that desliming affects flotation performance, an attempt was made to quantify the effects of the major influencing parameters on the effectiveness of desliming and flotation. Because the optimum collector dosage was found to be very high, the effects of addition of sodium oleate and Aero 3477 were also investigated, to reduce the collector dosage. However, flotation results showed that the addition of sodium oleate and Aero 3477 does not alter the collector dosage significantly. Despite all the aforementioned efforts, only 20% of feed ash could be removed. 相似文献
945.
946.
Muhammad Reazul Haque Saw Chin Tan Zulfadzli Yusoff Kashif Nisar Rizaludin Kaspin Iram Haider Sana Nisar J. P. C. Rodrigues Bhawani Shankar Chowdhry Muhammad Aslam Uqaili Satya Prasad Majumder Danda B. Rawat Richard Etengu Rajkumar Buyya 《计算机、材料和连续体(英文)》2022,70(1):875-894
In the design and planning of next-generation Internet of Things (IoT), telecommunication, and satellite communication systems, controller placement is crucial in software-defined networking (SDN). The programmability of the SDN controller is sophisticated for the centralized control system of the entire network. Nevertheless, it creates a significant loophole for the manifestation of a distributed denial of service (DDoS) attack straightforwardly. Furthermore, recently a Distributed Reflected Denial of Service (DRDoS) attack, an unusual DDoS attack, has been detected. However, minimal deliberation has given to this forthcoming single point of SDN infrastructure failure problem. Moreover, recently the high frequencies of DDoS attacks have increased dramatically. In this paper, a smart algorithm for planning SDN smart backup controllers under DDoS attack scenarios has proposed. Our proposed smart algorithm can recommend single or multiple smart backup controllers in the event of DDoS occurrence. The obtained simulated results demonstrate that the validation of the proposed algorithm and the performance analysis achieved 99.99% accuracy in placing the smart backup controller under DDoS attacks within 0.125 to 46508.7 s in SDN. 相似文献
947.
Precision Additive Nanofabrication: The Role of Liquid Ink Transport in the Direct Placement of Quantum Dot Emitters onto Sub‐Micrometer Antennas by Dip‐Pen Nanolithography (Small 31/2018) 下载免费PDF全文
948.
Silicon doped SnO2 films were synthesized by sputtering SnO2 layer onto glass substrates with appropriate amount of silicon sputtered onto them. The bilayer structures were subjected to rapid thermal annealing for the incorporation of Si in SnO2 matrix. The films thus obtained were characterized by measuring optical and microstructural properties. Liquid petroleum gas (LPG) sensing properties were also investigated. FTIR and Raman studies were also carried out on these films, both, before and after LPG exposure. 相似文献
949.
This paper presents the observations of the study on arsenic removal from a contaminated ground water (simulated) by adsorption onto Fe3+ impregnated granular activated carbon (GAC-Fe). Fe2+, Fe3+ and Mn2+ have also been considered along with arsenic species in the water sample. Similar study has also been done with untreated granular activated carbon (GAC) for comparison. The effects of adsorbent dose, particle size of adsorbent and initial arsenic concentration on the removal of As(T), As(III), As(V), Fe2+, Fe3+ and Mn2+ have been discussed. Under the experimental conditions, the optimum adsorbent doses for GAC-Fe and GAC have been found to be 8 g/l and 24 g/l, respectively with an agitation time of 15 h. Particle size of the adsorbents (both GAC and GAC-Fe) has shown negligible effect on the removal of arsenic and Fe species. However, for Mn removal the effect of adsorbent particle size is comparatively more. Percentage removal of As(T), As(V) and As(III) increase with the decrease in initial arsenic concentration (As0). However, the increase in percentage removal of all the arsenic species with decrease in As0 are less for higher value of As0 (3000–500 ppb) than those of the lower value of As0 (500–10 ppb). The % removal of As(T), As(III), As(V), Fe, and Mn were 95%, 92.4%, 97.6%, 99% and 41.2%, respectively when 8 g/l GAC-Fe was used at the As0 value of 200 ppb. However, for GAC these values were 55.5%, 44%, 71%, 98% and 97%. The pH and temperature of the study were 7 ± 0.1 and 30 ± 1 °C, respectively. 相似文献
950.
For better quality of life (QoL) for the cancer patients, metronomic chemotherapy (MCT) would be the rational option instead of conventional chemotherapy. However, in view of the recent arguments regarding the accumulation of toxicity in MCT, it is worthwhile to examine the role of pathophysiological constraints in retarding the curative potential of MCT. Drug application is stopped upon attaining a certain high level of toxicity and subsequent resumption is possible once the toxicity drops below a certain low level. Large delays in subsequent drug administration can thus effectively handle toxicity and it may retard the therapeutic potential due to excessive tumour growth in the absence of drug. Small delays, on the other hand, may result in inoperable pathophysiological states resulting in poor QoL. It is argued that only the intervention of domain knowledge of an expert oncologist with respect to drug administration decision can in fact clinch the trade-off issues arising out of the situation in favour of a sustainable QoL. A mathematical model that may act as a general guideline to tackle the trade-off issues in cancer treatment is provided. Rigorous simulation exercises are required to establish the concept of MCT in the backdrop of conventional cancer treatment practices. 相似文献