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1.
Sequencing of rice genome has facilitated the understanding of rice evolution and has been utilized extensively for mining of DNA markers to facilitate marker-assisted breeding. Simple sequence repeat (SSR) markers that are tandemly repeated nucleotide sequence motifs flanked by unique sequences are presently the maker of choice in rice improvement due to their abundance, co-dominant inheritance, high levels of allelic diversity, and simple reproducible assay. The current level of genome coverage by SSR markers in rice is sufficient to employ them for genotype identification and marker-assisted selection in breeding for mapping of genes and quantitative trait loci analysis. This review provides comprehensive information on the mapping and applications of SSR markers in investigation of rice cultivars to study their genetic divergence and marker-assisted selection of important agronomic traits.  相似文献   
2.
Five studies examined whether spontaneous trait inferences uniquely reference the person who performed a trait-implying behavior. On each study trial in 5 studies, participants saw 2 faces and a behavioral sentence referring to one of them. Later, participants saw face-trait pairs and indicated whether they had seen the trait word in the sentence presented with the face. Participants falsely recognized implied traits more when these traits were paired with actors' faces than with control faces. This effect was replicated for a large set effaces (120), after a week delay between study and recognition test, when equal attention was paid to each face, and when the orientation of the face at recognition was different from the orientation at encoding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
This study examined the degree to which different types of communication disturbances in the speech of 48 schizophrenia patients and 28 controls were variable and state related versus stable and traitlike. Clinically rated formal thought disorder and 5 types of referential disturbance showed substantial stability within participants over time. The sixth type of referential disturbance, the vague reference, was not stable over time. Formal thought disorder was associated with the severity of core psychotic symptoms in patients, whereas referential disturbances showed little or no association with positive or negative symptom severity. Furthermore, changes in psychotic symptoms over time were accompanied by corresponding changes in formal thought disorder but not referential disturbances. These results support the idea that some types of referential disturbances are traitlike and may be reflective of vulnerability as well as manifest illness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
G. J. DuPaul (see record 2003-02033-012) offered two suggestions for additional research to understand the strong source effects reported by R. Gomez, G. L Burns, J. A. Walsh, and M. A. de Moura (see record 2003-02033-001) in attention-deficit/ hyperactivity disorder (ADHD) rating scales. The first suggestion was to determine whether the source effects represent mostly bias or accuracy. The second suggestion was to minimize source effects through the development of better ADHD rating scales. Because source effects can represent bias or accuracy, it is important to minimize the bias aspect through content validation procedures prior to attempts to determine whether source effects better reflect bias or accuracy. This comment offers various suggestions to reduce the bias in ADHD rating scales. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
Tomato is one of the major vegetable crops consumed worldwide. Tomato yellow leaf curl virus (TYLCV) and fungal Oidium sp. are devastating pathogens causing yellow leaf curl disease and powdery mildew. Such viral and fungal pathogens reduce tomato crop yields and cause substantial economic losses every year. Several commercial tomato varieties include Ty-5 (SlPelo) and Mildew resistance locus o 1 (SlMlo1) locus that carries the susceptibility (S-gene) factors for TYLCV and powdery mildew, respectively. The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas) is a valuable genome editing tool to develop disease-resistant crop varieties. In this regard, targeting susceptibility factors encoded by the host plant genome instead of the viral genome is a promising approach to achieve pathogen resistance without the need for stable inheritance of CRISPR components. In this study, the CRISPR/Cas9 system was employed to target the SlPelo and SlMlo1 for trait introgression in elite tomato cultivar BN-86 to confer host-mediated immunity against pathogens. SlPelo-knockout lines were successfully generated, carrying the biallelic indel mutations. The pathogen resistance assays in SlPelo mutant lines confirmed the suppressed accumulation of TYLCV and restricted the spread to non-inoculated plant parts. Generated knockout lines for the SlMlo1 showed complete resistance to powdery mildew fungus. Overall, our results demonstrate the efficiency of the CRISPR/Cas9 system to introduce targeted mutagenesis for the rapid development of pathogen-resistant varieties in tomato.  相似文献   
6.
As a first step toward understanding how noctuid moths evolve species-specific pheromone communication systems, we hybridized and backcrossed two closely related moth species, Heliothis virescens (Hv) and H. subflexa (Hs), which differ qualitatively and quantitatively in their multi-component sex pheromone blends. We used amplified fragment length polymorphism (AFLP) marker-based mapping of backcross families to determine which of the 30 autosomes in these moths contained quantitative trait loci (QTL) controlling the percentages of specific chemical components in the pheromone blends. In two previous backcrosses to Hs, we found a strong depressive effect of Hv-chromosome 22 on the percentage of three acetate components in the pheromone gland. These acetates are present in Hs and absent in Hv. Here, we describe how we introgressed Hv-chromosome 22 into the genomic background of Hs. Selection for Hv-chromosome 22 started from backcross 3 (BC3) females. All females that had Hv-chromosome 22 and a low percentage of acetates (< 3% of the total amount of pheromone components present) were backcrossed to Hs males. In BC5 to BC8, we determined whether Hv-chromosome 22 was present by a) running only the primer pairs that would yield the markers for that chromosome, and/or b) determining the relative percentages of acetates in the pheromone glands. Either or both genotype and phenotype were used as a criterion to continue to backcross these females to Hs males. In BC9, we confirmed the isolation of Hv-chromosome 22 in the Hs genomic background, and backcrossed the males to Hs females to eliminate the Hv-sex chromosome as well as mitochondrial DNA. The pheromone composition was determined in BC3, BC5, and BC11 females with and without Hv-chromosome 22. All backcross females with Hv-chromosome 22 contained significantly less acetates than females without this chromosome. In addition, BC3 females with Hv-chromosome 22 contained significantly more Z11-16:OH than BC3 females without Hv-chromosome 22. However, in BC5 and BC11 females, the correlation between Z11-16:OH and Hv-chromosome 22 was lost, suggesting that there are separate QTL for the acetates and for Z11-16:OH, and that the relative amount of the alcohol component is only affected in epistasis with other (minor) QTL. Now that we have succeeded in isolating the chromosome that has a major effect on acetate production, we can test in behavioral experiments whether the presence of acetates may have been a driving force for a shift in pheromone composition. Such tests are necessary to move towards an evolutionary understanding of the differentiation in sexual communication in Heliothis spp. moths.  相似文献   
7.
随着计算机科学的迅猛发展和工程力学有限元分析理论的不断成熟,空气弹簧的设计和开发由早期主要依靠试验和实际运用中得到的数据来改进转向了计算机虚拟设计与试验相结合的渠道上来.本文运用CAD软件建立了空气弹簧系统的三维立体模型,通过有限元分析,建立了空气弹簧系统的有限元模型,并进行了垂向力学特性分析,其结果与试验结果相一致,为空气弹簧的设计和制造提供了有益的参考.  相似文献   
8.
Student modelling is an important process for adaptive virtual learning environments. Student models include a range of information about the learners such as their domain competence, learning style or cognitive traits. To be able to adapt to the learners’ needs in an appropriate way, a reliable student model is necessary, but getting enough information about a learner is quite challenging. Therefore, mechanisms are needed to support the detection process of the required information. In this paper, we investigate the relationship between learning styles, in particular, those pertaining to the Felder–Silverman learning style model and working memory capacity, one of the cognitive traits included in the cognitive trait model. The identified relationship is derived from links between learning styles, cognitive styles, and working memory capacity which are based on studies from the literature. As a result, we demonstrate that learners with high working memory capacity tend to prefer a reflective, intuitive, and sequential learning style whereas learners with low working memory capacity tend to prefer an active, sensing, visual, and global learning style. This interaction can be used to improve the student model. Systems which are able to detect either only cognitive traits or only learning styles retrieve additional information through the identified relationship. Otherwise, for systems that already incorporate learning styles and cognitive traits, the interaction can be used to improve the detection process of both by including the additional information of a learning style into the detection process of cognitive traits and vice versa. This leads to a more reliable student model.  相似文献   
9.
谢柏林  黎琦  魏娜  邝建 《计算机工程》2023,49(1):279-286+294
社交网络已成为人们获取和发布信息的一个重要平台,也是黑客发起网络诈骗的主要场地。大多数黑客在发起网络诈骗之前,首先会判别目标用户的主要人格特点,然后根据主要人格特点制定与其接触的策略。因此,面向社交网络用户的人格特质识别方法的研究对提高用户识别社交网络诈骗能力具有重要意义。提出基于用户的人格特质识别方法。通过构建面向社交网络的人格特质词典提取用户发表或转发文本信息中能反映用户主要人格特质类型的观测值,采用5个具有不同参数值的隐半马尔可夫模型刻画用户在社交网络上发表或转发文本信息的行为过程。在人格特质识别阶段,通过计算每个用户在发表或转发文本信息过程中产生的观测序列相对于模型的平均对数似然概率,以识别用户所属的人格特质类型。在采集的新浪微博数据集上进行实验,结果表明,当假正率为10%时,该方法的总真正率为93.18%,能准确识别用户的人格特质类型。  相似文献   
10.
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