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Thirty-four (8%) of 453 infants and children with urinary system malformations had cardiovascular malformations. Cardiac defects were seen frequently in Potter syndrome, unilateral renal agenesis, and horseshoe kidney. The most frequently encountered types of heart defects were ventricular septal defect (33%), endocardial cushion defect (15%), tetralogy of Fallot (12%), and patent ductus arteriosus (12%).  相似文献   
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Four series of new 1,2,4‐oxadiazole derived bent‐core liquid crystals incorporating one or two cyclohexane rings are synthesized and investigated by optical polarizing microscopy, differential scanning calorimetry (DSC), X‐ray diffraction (XRD), electro‐optical, and dielectric investigations. All the compounds exhibit wide ranges of nematic phases composed of tilted smectic (SmC‐type) cybotactic clusters with strongly tilted aromatic cores (40–57°) and show a distinct peak in the current curves observed under a triangular wave field. Dielectric spectroscopy of aligned samples corroborates the previously proposed polar structure of the cybotactic clusters and the ferroelectric‐like polar switching of these nematic phases. Hence, it is shown that this is a general feature of the nematic phases of structurally different 3,5‐diphenyl‐1,2,4‐oxadiazole derivatives. In these uniaxial nematic phases there is appreciable local biaxiality and polar order in the cybotactic clusters. As a second point it is shown that electric field induced fan‐like textures, as often observed for the nematic phases of bent‐core liquid crystals, do not indicate the formation of a smectic phase, rather they represent special electro‐convection patterns due to hydrodynamic instabilities.  相似文献   
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Increased gut permeability is suggested to be involved in the pathogenesis of a growing number of disorders. The altered intestinal barrier and the subsequent translocation of bacteria or bacterial products into the internal milieu of the human body induce the inflammatory state. Gut microbiota maintains intestinal epithelium integrity. Since dysbiosis contributes to increased gut permeability, the interventions that change the gut microbiota and correct dysbiosis are suggested to also restore intestinal barrier function. In this review, the current knowledge on the role of biotics (probiotics, prebiotics, synbiotics and postbiotics) in maintaining the intestinal barrier function is summarized. The potential outcome of the results from in vitro and animal studies is presented, and the need for further well-designed randomized clinical trials is highlighted. Moreover, we indicate the need to understand the mechanisms by which biotics regulate the function of the intestinal barrier. This review is concluded with the future direction and requirement of studies involving biotics and gut barrier.  相似文献   
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Abstract— High‐power red, green, and blue laser light sources made from vertically emitting arrays of intracavity doubled IR lasers is reported. The emitted infrared light from a monolithic array of large‐aperture vertical cavity lasers is converted into visible light using a PPLN doubling crystal in an external cavity. A volume Bragg grating provides simultaneous feedback for all emitters in the array and sets the laser wavelength. Increased diffraction losses for higher‐order modes result in quasi‐Gaussian beams with excellent conversion efficiency. Green 532‐nm lasers with more than 5.8‐W visible power have been demonstrated at a base temperature of 40°C. Blue 465‐nm lasers with 4.4‐W power at 40°C are unmatched in performance and wavelength when compared to competing GaN‐based edge emitters. Typical wall‐plug efficiencies are higher than 8%. We have measured single‐emitter operating lifetimes to be more than 28,000 hours. Red lasers based on highly strained InGaAs achieve record laser powers of 2.0W at 618 nm in the same form factor as the green and blue lasers. Red single‐emitter lifetimes of more than 10,000 hours have been attained. The technology described in this paper delivers on a full suite of cost efficient and reliable red, green, and blue lasers that meet the demands of the display markets.  相似文献   
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Listeria spp. are ubiquitously found in both the natural and the food processing environment, of which Listeria monocytogenes is of an important health risk. Here, we report on the formation of single and mixed species biofilms of L. monocytogenes/Listeria innocua and Lactobacillus plantarum strains in 24‐well polystyrene microtiter plates and on the inactivation of 24‐hr and 72‐hr biofilms using quaternary ammonium compound‐, tertiary alkyl amine‐, and chlorine‐based disinfectants. Fluorescent in situ hybridization (FISH) and LIVE/DEAD BacLight staining were applied for 72‐hr L. innocuaL. plantarum mixed biofilms in the LabTek system for the species identification and the reaction of biofilm cells to disinfectants, respectively. L. monocytogenes/L. innocua were more resistant to disinfectants in 72‐hr than in 24‐hr biofilms, whereas L. plantarum strains did not show any significant differences between 72‐hr and 24‐hr biofilms. Furthermore, L. innocua when grown with L. plantarum was more resistant to all disinfection treatments, indicating a protective effect from lactobacilli in the mixed species biofilm. The biofilm formation and reaction to disinfectants, microscopically verified using fluorescence in situ hybridization and LIVE/DEAD staining, showed that L. innocua and L. plantarum form a dense mixed biofilm and also suggested the shielding effect of L. plantarum on L. innocua in the mixed species biofilm.  相似文献   
7.
Infrared spectroscopy (IR) and quantum chemistry calculations that are based on the density functional theory (DFT) have been used to study the structure and molecular interactions of the nematic and twist-bend phases of thioether-linked dimers. Infrared absorbance measurements were conducted in a polarized beam for a homogeneously aligned sample in order to obtain more details about the orientation of the vibrational transition dipole moments. The distributions to investigate the structure and conformation of the molecule dihedral angle were calculated. The calculated spectrum was compared with the experimental infrared spectra and as a result, detailed vibrational assignments are reported.  相似文献   
8.
Continuous-wave operation of etched-facet InGaN/GaN multiquantum-well ridge-waveguide laser diodes grown by low pressure MOVPE on a sapphire substrate has been achieved on-wafer for >2 min at 15% above threshold. The threshold current density and voltage were 9.1 kA/cm2 and 7.6 V, respectively, at 15°C, and the lasing wavelength was 400.6 nm  相似文献   
9.
Modulation-doped field-effect transistors (MODFETs) exhibit transient responses that contain a variety of time constants. The strongest transients observed in the microsecond range are known to be caused by the DX centers. MODFETs also suffer a transient that arises from a source different from that of the DX centers. Preliminary measured characteristics of the nanosecond transient are presented, its effects on circuit performance are described, and its possible origin is inferred  相似文献   
10.
One of the biggest challenges faced by food producers is ensuring microbiological safety. Despite strict criteria for food products, foodborne diseases are a global problem and pose a real risk to consumers. Therefore, it is necessary to identify new and more effective methods for eliminating pathogens from food and the food processing environment. According to the European Food Safety Authority (EFSA), the most common foodborne diseases are caused by Campylobacter, Salmonella, Yersinia, Escherichia coli, and Listeria. Out of the five listed, four are Gram-negative bacteria. Our review focuses on the use of bacteriophages, which are ubiquitous bacterial viruses, and bacteriophage endolysins to eliminate Gram-negative pathogens. Endolysins cleave specific bonds within the peptidoglycan (PG) of the bacterial cell, causing the cell to burst. Single phages or phage cocktails, which are, in some instances, commercially available products, eliminate pathogenic bacteria in livestock and various food matrices. Endolysins have matured as the most advanced class of antibacterial agents in the clinical sector, but their use in food protection is highly unexplored. Advanced molecular engineering techniques, different formulations, protein encapsulation, and the addition of outer membrane (OM) permeabilization agents enhance the activity of lysins against Gram-negative pathogens. This creates space for groundbreaking research on the use of lysins in the food sector.  相似文献   
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