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21.
DENS: data center energy-efficient network-aware scheduling   总被引:1,自引:0,他引:1  
In modern data centers, energy consumption accounts for a considerably large slice of operational expenses. The existing work in data center energy optimization is focusing only on job distribution between computing servers based on workload or thermal profiles. This paper underlines the role of communication fabric in data center energy consumption and presents a scheduling approach that combines energy efficiency and network awareness, named DENS. The DENS methodology balances the energy consumption of a data center, individual job performance, and traffic demands. The proposed approach optimizes the tradeoff between job consolidation (to minimize the amount of computing servers) and distribution of traffic patterns (to avoid hotspots in the data center network).  相似文献   
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Nano materials with high surface area increase the kinetics and extent of the redox reactions, thus resulting in high power and energy densities. In this study high surface area zinc oxide nanorods have been synthesized by surfactant free ethylene glycol assisted solvothermal method. The nanorods thus prepared have diameters in the submicron range (300∼500 nm) with high aspect ratio. They have uniform geometry and well aligned direction. These nanorods are characterized by XRD, SEM, Specific Surface Area Analysis, solubility in alkaline medium, EDX analysis and galvanostatic charge/discharge studies in Zn/AgO batteries. The prepared zinc oxide nanorods have low solubility in alkaline medium with higher structural stability, which imparts the improved cycle life stability to Zn/AgO cells.  相似文献   
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Plants frequently suffer from environmental stresses in nature and have evolved sophisticated and efficient mechanisms to cope with the stresses. To balance between growth and stress response, plants are equipped with efficient means to switch off the activated stress responses when stresses diminish. We previously revealed such an off-switch mechanism conferred by Arabidopsis PARAQUAT TOLERANCE 3 (AtPQT3) encoding an E3 ubiquitin ligase, knockout of which significantly enhances resistance to abiotic stresses. To explore whether the rice homologue OsPQT3 is functionally conserved, we generated three knockout mutants with CRISPR-Cas9 technology. The OsPQT3 knockout mutants (ospqt3) display enhanced resistance to oxidative and salt stress with elevated expression of OsGPX1, OsAPX1 and OsSOD1. More importantly, the ospqt3 mutants show significantly enhanced agronomic performance with higher yield compared with the wild type under salt stress in greenhouse as well as in field conditions. We further showed that OsPQT3 expression rapidly decreased in response to oxidative and other abiotic stresses as AtPQT3 does. Taken together, these results show that OsPQT3 is functionally well conserved in rice as an off-switch in stress response as AtPQT3 in Arabidopsis. Therefore, PQT3 locus provides a promising candidate for crop improvement with enhanced stress resistance by gene editing technology.  相似文献   
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Journal of Plant Growth Regulation - Despite the plethora of published reports on ameliorative effects of exogenously applied salicylic acid (SA) to plants under salt stress, a critical role of SA...  相似文献   
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Sustainable rice production through selection of best suitable cultivar, water-efficient crop establishment method and optimum nitrogen (N) management practice is needed to feed the growing world population. Two polyhouse experiments were conducted to evaluate the response of rice to different rates and schedules of N application under different establishment methods subjected to alternate wetting and drying (AWD) irrigation. In the first experiment, the response of two rice cultivars (Pathumthani 1, RD57) under three establishment methods (transplanting [TP], wet direct seeding [WDS], dry direct seeding [DDS]) and five N rates (0 [N0], 30 [N30], 60 [N60], 90 [N90], 120 [N120] kg ha−1) was evaluated. The second experiment consisted of the same cultivars and establishment methods, but with four N application schedules (T1: 100% at basal; T2: 75% + 25% at basal and at active tillering, respectively; T3: 50% + 25% + 25% at basal, at active tillering and at panicle initiation, respectively; and T4: 25% + 25% + 25% + 25% each at basal, at active tillering, at panicle initiation and at early flowering or just before heading starts) applied at the rate of N60 kg ha−1. Plants were maintained under AWD irrigation (soil was saturated by applying water whenever soil water potential drops to −5 kPa during the implementation period) in both experiments. RD57 performed better than Pathumthani 1 having higher shoot dry matter, panicle number, grain yield, total N uptake and apparent N recovery efficiency. TP gave better response than WDS and DDS regardless of cultivars. Application of N120 resulted in better growth, yield and its components and total N uptake regardless of establishment methods and cultivars. Increasing N rate decreased N use efficiency (NUE). Scheduling the interval of N application to two or three times (T2 or T3) for RD57 and Pathumthani 1, respectively, provided overall better results, and could be recommended for the tested rice cultivars. An optimal N rate and selection of critical growth stages for N application would be very effective for maximising yield and NUE under the water-saving cultivation technique of AWD irrigation.  相似文献   
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Background

Limited health facilities and malnutrition are major problems in the Karakorum Range of Northern Pakistan, often resulting in various human disorders. Since centuries, however, local communities in these areas have developed traditional methods for treating various ailments and local foods capes that can be significant for devising public health and nutritional policies. This study was intended to document the ethnobotanical knowledge of the local peoples in the Tormik Valley, especially in the medical and food domains.

Methods

Field trips were undertaken in 14 different villages of the study area from 2010 to 2012. Ethnobotanical data were gathered using semi-structured interviews and group conversation with 69 informants. Details about local uses of plant species were recorded along with demographic characteristics of the visited communities. Relative frequency citation index (RFCi) and preference ranking index (PRi) tools were applied to determine the cultural significance of the reported species.

Results

Sixty-three plant species, with a predominance of Asteraceae and Fabaceae family members, as well as their detailed folk uses were documented. Forty-three percent of the species were used to treat various diseases, 21 % were consumed as wild fruits and vegetables and 53 % of the species had multipurpose applications. Thymus linearis Benth, Hippophae rhamnoides ssp. turkestanica L. and Convolvulus arvensis L. were found to be the most utilized medicinal plant species, i.e. those with significant RFCi values (0.54, 0.51 and 0.48, respectively). Betula utilis D. Don was the most versatile taxon (seven different ways of utilization); being this species a common and easily accessible subalpine tree and then under anthropogenic pressure, the implementation of concrete strategies aimed at its in-situ and ex-situ conservation is strongly recommended.

Conclusion

The valleys in the Karakorum Mountains in the Northern Pakistan host significant Traditional Knowledge on local food and medicinal plant species, which need to be reconsidered and cautiously re-evaluated by ethnopharmacologists, and public health/nutrition actors. Furthermore, germane trans-disciplinary investigations are suggested to ensure the dynamic conservation of precious local knowledge systems, as well as plant diversity in Pakistani mountain regions.
  相似文献   
29.
Copper oxide nanomaterials were synthesized by a facile sustainable biological method using two plant species (Zanthoxylum armatum DC. and Berberis lycium Royle ). The formation of materials was confirmed by FT‐IR, ATR, UV‐visible, XRD, TEM, SEM, EDX, TGA and PL. The antibacterial activity was evaluated by agar well diffusion method to ascertain the efficacy of plant species extract and extract derived copper oxide nanomaterials against six Gram‐positive bacteria namely Staphylococcus aureus, Streptococcus mutans, Streptococcus pyogenes, Corynebacterium diphtheriae, Corynebacterium xerosis, Bacillus cereus and four Gram‐negative bacteria such as Klebsiella pneumonia, Escherichia coli, Pseudomonas aeruginosa and Proteus vulgaris against the standard drug, Ciprofloxacin for Gram‐positive and Gentamicin for Gram‐negative bacteria, respectively. In both cases, copper oxide nanomaterials were found to be sensitive in all the bacterial species. Sensitivity of copper oxide nanomaterials shows an be higher as compared to plant species extract against different bacteria. Scavenging activity of plant extracts along with nanomaterials have been accessed using previously reported protocols employing ascorbic acid as standard. Scavenging activity of copper oxide nanomaterials shows an increase with increase in concentration. The biological activity (bactericidal and scavenging efficiency) of plant derived copper oxide nanomaterials revealed that these materials can be used as potent antimicrobial agent and DPPH scavengers in industrial as well as pharmacological fields.  相似文献   
30.
ObjectiveMaize is an important crop for fodder, food and feed industry. The present study explores the plant-microbe interactions as alternative eco-friendly sustainable strategies to enhance the crop yield.MethodologyBacterial diversity was studied in the rhizosphere of maize by culture-dependent and culture-independent techniques by soil sampling, extraction of DNA, amplification of gene of interest, cloning of desired fragment and library construction.ResultsCulturable bacteria were identified as Achromobacter, Agrobacterium, Azospirillum, Bacillus, Brevibacillus, Bosea, Enterobacter, Microbacterium, Pseudomonas, Rhodococcus, Stenotrophomonas and Xanthomonas genera. For culture-independent approach, clone library of 16S ribosomal RNA gene was assembled and 100 randomly selected clones were sequenced. Majority of the sequences were related to Firmicutes (17%), Acidobacteria (16%), Actinobacteria (17%), Alpha-Proteobacteria (7%), Delta-proteobacteria (4.2%) and Gemmatimonadetes (4.2%) However, some of the sequences (30%) were novel that showed no homologies to phyla of cultured bacteria in the database. Diversity of diazotrophic bacteria in the rhizosphere investigated by analysis of PCR-amplified nifH gene sequence that revealed abundance of sequences belonging to genera Azoarcus (25%), Aeromonas (10%), Pseudomonas (10%). The diazotrophic genera Azotobacter, Agrobacterium and Zoogloea related nifH sequences were also detected but no sequence related to Azospirillum was found showing biasness of the growth medium rather than relative abundance of diazotrophs in the rhizosphere.ConclusionThe study provides a foundation for future research on focussed isolation of the Azoarcus and other diazotrophs found in higher abundance in the rhizosphere.  相似文献   
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