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61.
In this work, we demonstrate an integrated, single-layer, miniature flow cytometry device that is capable of multi-parametric particle analysis. The device integrates both particle focusing and detection components on-chip, including a “microfluidic drifting” based three-dimensional (3D) hydrodynamic focusing component and a series of optical fibers integrated into the microfluidic architecture to facilitate on-chip detection. With this design, multiple optical signals (i.e., forward scatter, side scatter, and fluorescence) from individual particles can be simultaneously detected. Experimental results indicate that the performance of our flow cytometry chip is comparable to its bulky, expensive desktop counterpart. The integration of on-chip 3D particle focusing with on-chip multi-parametric optical detection in a single-layer, mass-producible microfluidic device presents a major step towards low-cost flow cytometry chips for point-of-care clinical diagnostics.  相似文献   
62.
In this work, we demonstrate an integrated, single-layer, miniature flow cytometry device that is capable of multi-parametric particle analysis. The device integrates both particle focusing and detection components on-chip, including a "microfluidic drifting" based three-dimensional (3D) hydrodynamic focusing component and a series of optical fibers integrated into the microfluidic architecture to facilitate on-chip detection. With this design, multiple optical signals (i.e., forward scatter, side scatter, and fluorescence) from individual particles can be simultaneously detected. Experimental results indicate that the performance of our flow cytometry chip is comparable to its bulky, expensive desktop counterpart. The integration of on-chip 3D particle focusing with on-chip multi-parametric optical detection in a single-layer, mass-producible microfluidic device presents a major step towards low-cost flow cytometry chips for point-of-care clinical diagnostics.  相似文献   
63.
Electrorotation is widely used for characterization of biological cells and materials using a rotating electric field. Generally, multiphase AC electric fields and quadrupolar electrode configuration are needed to create a rotating electric field for electrorotation. In this study, we demonstrate a simple method to rotate dielectrophoretically trapped microparticles using a stationary AC electric field. Coplanar interdigitated electrodes are used to create a linearly polarized nonuniform AC electric field. This nonuniform electric field is employed for dielectrophoretic trapping of microparticles as well as for generating electroosmotic flow in the vicinity of the electrodes resulting in rotation of microparticles in a microfluidic device. The rotation of barium titanate microparticles is observed in 2-propanol and methanol solvent at a frequency below 1 kHz. A particle rotation rate as high as 240 revolutions per minute is observed. It is demonstrated that precise manipulation (both rotation rate and equilibrium position) of the particles is possible by controlling the frequency of the applied electric field. At low frequency range, the equilibrium positions of the microparticles are observed between the electrode edge and electrode center. This method of particle manipulation is different from electrorotation as it uses induced AC electroosmosis instead of electric torque as in the case of electrorotation. Moreover, it has been shown that a microparticle can be rotated along its own axis without any translational motion.  相似文献   
64.
Bahawa “bahasa” dalam pengertian orang-orang Melayu tidaklah semata-mata bersifat lingual (yang hanya menjadi alat komunikasi antara dua pihak pengguna bahasa sahaja); tetapi bahasa itu adalah lebih kultural (yang menjadi pengilham dan pendorong manusia ke tahap lebih baik dalam hidupnya; sekaligus mempertinggi kebudayaan manusia itu).  相似文献   
65.
66.
This study aimed at examining Jordanian pre-service special education teachers’ professionalism and preparation on the topic of child sexual abuse (CSA). Qualitative research data from interviews with 20 pre-service special education teachers were analysed using thematic analysis. The results showed that these participants generally hold avoiding behaviour toward speaking about CSA as it is an unspoken taboo. Participants also hold low levels of professionalism on the topic of CSA. The results also demonstrate that they felt that their preparation programme is inadequate and desired more content and pedagogy courses that relate to CSA. Implications and recommendations are presented in light of the study findings.  相似文献   
67.
Early Malaysian national cinema disseminates a social reconstruction process aimed at reconstructing Malay supremacy at the centre of a specific geographical, political, economic and cultural space. Aptly termed as ‘Malaynisation’, this process occurred during the Golden Age of Malaysian cinema through the films of P. Ramlee. While existing as a capitalist film culture located within an ethnically diverse society, early Malaysian cinema through Ramlee have produced a significant number of mono-ethnic representations solely focused on the culture, language and lifestyles of the Malays. As such, the articulation of the politics of inclusion and exclusion in Ramlee’s films articulates a right-wing nationalist sentiment that upholds the sovereignty of the dominant Malays while undermining other ethnic communities. The nature of these representations enunciates the context of an ‘imagined community’ which locates the formation of a particular type of nationalism within a social, political and cultural communicative space. This paper examines the construction of the ‘modern Malay’ identity in Ramlee’s films and the nationalist discourse in Ramlee’s films as an attempt at producing the idea of a nation as a continuous narrative of national progression by presenting the postcolonial Malays as a modern, successful and dominant force.  相似文献   
68.
This paper proposes a new multiuser communication model in which a source with broadcast capabilities wants to transmit two different messages to two different destinations in the case that no direct links between the source and its destinations. In this channel model, two parallel half-duplex relays are used to extend the transmission. For this communication model, an outer bound to the achievable capacity is initially derived. Then, two distinctive transmission schemes are characterized such that the source can transmit to the two destinations. In each scheme, the transmission is split into two phases. Specifically, in the first phase, the source can broadcast different messages to the two relays. Then, in the second phase, the two relays can forward the source’s signals into their destinations. Based on the transmission on each scheme, the achievable rate region is characterized. Further, we derive the optimal duration of each phase. The theoretical analyses are followed by many numerical examples that compare between the different transmission techniques and also show the points at which the capacity is achieved.  相似文献   
69.
Despite considerable research in advanced countries on public perceptions of and attitudes to modern biotechnology, limited effort has been geared towards developing a structural model of public attitudes to modern biotechnology. The purpose of this paper is to identify the relevant factors influencing public attitudes towards genetically modified (GM) soybean, and to analyze the relationship between all the attitudinal factors. A survey was carried out on 1,017 respondents from various stakeholder groups in the Klang Valley region. Results of the survey have confirmed that attitudes towards complex issues such as biotechnology should be seen as a multifaceted process. The most important factors predicting support for GM soybean are the specific application-linked perceptions about the benefits, acceptance of risk and moral concern while risk and familiarity are significant predictors of benefit and risk acceptance. Attitudes towards GM soybean are also predicted by several general classes of attitude.  相似文献   
70.
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