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81.
This paper considers interference characterization and management in wireless ad hoc networks using MIMO techniques. The power allocation in each link is built into a non-cooperative game where a utility function is identified and maximized. Due to poor channel conditions, some links have very low data transmission rates even though their transmit powers are high. Therefore, a mechanism for shutting down links is proposed in order to reduce cochannel interference and improve energy efficiency. The multiuser water-filling and the gradient projection methods are compared with the proposed game theoretic approach in terms of system capacity and energy efficiency. It is shown that using the proposed method with the link shut-down mechanism allows the MIMO ad hoc network to achieve the highest energy efficiency and the highest system capacity 相似文献
82.
Inorganic crystals grown from solution find wide application. A mechanistic growth model based on the spiral growth mechanism that operates at low supersaturation on inorganic crystal surfaces is presented. The long‐range electrostatic interactions on inorganic crystal surfaces are captured by methods developed in our previous article (Dandekar and Doherty, AIChE J., in press). The interactions of kink site growth units with the solvent molecules partially determine the growth kinetics. Relevant experimental parameters are systematically accounted for in the expression for the kink incorporation rate along step edges on the crystal surfaces. The growth model accurately predicts the asymmetric growth spirals on the surface of calcite crystals. The effect of supersaturation and ionic activity ratio on the step velocities of the acute and obtuse spiral edges is also correctly captured. This model can be used to predict the shapes of solution grown inorganic crystals and to engineer the growth process to design inorganic solids with functionally desirable shapes. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3720–3731, 2014 相似文献
83.
Milk protein gene expression in the rat mammary gland 总被引:1,自引:0,他引:1
P K Qasba A M Dandekar T M Horn I Losonczy M Siegel K A Sobiech H L Nakhasi E Devinoy 《Critical reviews in food science and nutrition》1982,16(2):165-186
For the studies of the expression of milk proteins during the functional development of the rat mammary gland and in mammary tumor MTW9, milk proteins were purified, their mRNAs isolated, and the cDNA sequences complementary to these mRNAs cloned in E. coli cells. Results of such studies show: (1) rat α‐LA is unique in that it is larger than any known α‐LAs and is glycosylated; (2) rat milk contains unique whey phosphoproteins not found in other milks; (3) more than one plasmid DNA with differences in the restriction maps have been identified for several of these milk proteins, suggesting eithera presence of a family of genes or allelic differences for these proteins; (4) the expression of individual milk proteins is dependent on the functional stage of the gland; (5) there is an inverse relationship between the expression of milk proteins and the methylation of their gene sequences; (6) mammotrophic hormones required for synthesis and stability of milk proteins and their mRNAs, when withdrawn arrest the synthesis of α‐LA in the mammary tumor MTW9 at 6 hr or earlier of withdrawal but without any measurable effect on other proteins of the tumor. 相似文献
84.
BACKGROUND: Hematopoietic abnormalities are a common complication of human immunodeficiency virus infection in humans. However, the pathogenesis of these abnormalities remains unclear. Simian immunodeficiency virus (SIV) infection of rhesus macaques is a well-recognized animal model for acquired immunodeficiency syndrome. Our previous studies have determined that in early SIV infection, rhesus macaques develop peripheral blood and bone marrow pathologic changes within the first 14 days after intravenous inoculation. Further investigations were initiated to determine the onset of bone marrow viral infection and the identity of in vivo viral cellular targets in bone marrow during the primary phase of infection in macaques infected with three different strains of SIVmac. EXPERIMENTAL DESIGN: Rhesus macaques experimentally infected with pathogenic uncloned biologic SIVmac, molecularly cloned pathogenic SIVmac-239, or nonpathogenic SIVmac-1A11 were studied at 3, 7, and 14 days postinoculation. Bone marrow samples taken at necropsy were examined to identify early in vivo cellular targets of SIVmac in bone marrow and to correlate hematopathologic lesions with viral infection. In the first 2 weeks after intravenous inoculation, cellular targets of viral infection were identified by a combined in situ hybridization/immunohistochemical technique; changes in bone marrow monocyte/macrophage and CD3+ T lymphocyte populations were evaluated by immunohistochemical techniques. RESULTS: SIV-infected monocyte/macrophages were detected on days 3, 7, and 14 days postinoculation in bone marrow of all monkeys regardless of the viral isolate, whereas only a few SIV-infected CD3+ T lymphocytes were detected in 5 of 18 monkeys. The bone marrow morphologic changes associated with acute SIV infection included macrophage hyperplasia and apparent macrophage activation, diminution of bone marrow T lymphocytes, appearance of lymphoid aggregates, and myeloid and megakaryocytic hyperplasia. CONCLUSIONS: We conclude that bone marrow monocyte/macrophages are an important early cellular target in SIV infection regardless of viral pathogenicity and in vitro cellular tropism. SIV-infected bone marrow monocyte/macrophages may play a key role in the pathogenesis of bone marrow lesions and further dissemination and persistence of virus infection. 相似文献
85.
Shishir K. Gupta Rashmi Minocha Prithivi Jung Thapa Mugdha Srivastava Thomas Dandekar 《International journal of molecular sciences》2022,23(16)
After the recent emergence of SARS-CoV-2 infection, unanswered questions remain related to its evolutionary history, path of transmission or divergence and role of recombination. There is emerging evidence on amino acid substitutions occurring in key residues of the receptor-binding domain of the spike glycoprotein in coronavirus isolates from bat and pangolins. In this article, we summarize our current knowledge on the origin of SARS-CoV-2. We also analyze the host ACE2-interacting residues of the receptor-binding domain of spike glycoprotein in SARS-CoV-2 isolates from bats, and compare it to pangolin SARS-CoV-2 isolates collected from Guangdong province (GD Pangolin-CoV) and Guangxi autonomous regions (GX Pangolin-CoV) of South China. Based on our comparative analysis, we support the view that the Guangdong Pangolins are the intermediate hosts that adapted the SARS-CoV-2 and represented a significant evolutionary link in the path of transmission of SARS-CoV-2 virus. We also discuss the role of intermediate hosts in the origin of Omicron. 相似文献