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81.

1. 1.The bahavioural paradigm in which cold-exposed animals can work for pulses of infrared radiation has been extensively used in the literature, but a formula to calculate the amount of heat obtained has not been advanced.

2. 2.This paper describes a computational formula for heat influx in rats: E = 3.64 · 10−6 · n · d · I · M0.6 where E is heat influx (kJ), n is number of rewards, d is reward duration (sec), I is irradiance (mW/cm2), and M is body mass (g).

Author Keywords: Heat influx; behavioural thermoregulation; thermal radiation; whole body heating; heat transfer; rat  相似文献   

82.
83.
Solar vaporization has received tremendous attention for its potential in desalination, sterilization, distillation, etc. However, a few major roadblocks toward practical application are the high cost, process intensive, fragility of solar absorber materials, and low efficiency. Herein an inexpensive cellular carbon sponge that has a broadband light absorption and inbuilt structural features to perform solitary heat localization for in situ photothermic vaporization is reported. The defining advantages of elastic cellular porous sponge are that it self‐confines water to the perpetually hot spots and accommodates cyclical dynamic fluid flow‐volume variable stress for practical usage. By isolating from bulk water, the solar‐to‐vapor conversion efficiency is increased by 2.5‐fold, surpassing that of conventional bulk heating. Notably, complementary solar steam generation‐induced electricity can be harvested during the solar vaporization so as to capitalize on waste heat. Such solar distillation and waste heat‐to‐electricity generation functions may provide potential opportunities for on‐site electricity and fresh water production for remote areas/emergency needs.  相似文献   
84.
A new procedure was used to conjugate lactose and dextran with BSA without using coupling or activating reagents. The method is simple, rapid and cheap. Reducing sugars covalently bind to proteins when lyophilized together and briefly heated to a high temperature.  相似文献   
85.
The interest in improving the yield and productivity values of relevant microbial fermentations is an increasingly important issue for the scientific community. Therefore, several strategies have been tested for the stimulation of microbial growth and manipulation of their metabolic behavior. One promising approach involves the performance of fermentative processes during non-conventional conditions, which includes high pressure (HP), electric fields (EF) and ultrasound (US). These advanced technologies are usually applied for microbial inactivation in the context of food processing. However, the approach described in this study focuses on the use of these technologies at sub-lethal levels, since the aim is microbial growth and fermentation under these stress conditions. During these sub-lethal conditions, microbial strains develop specific genetic, physiologic and metabolic stress responses, possibly leading to fermentation products and processes with novel characteristics. In some cases, these modifications can represent considerable improvements, such as increased yields, productivities and fermentation rates, lower accumulation of by-products and/or production of different compounds. Although several studies report the successful application of these technologies during the fermentation processes, information on this subject is still scarce and poorly understood. For that reason, the present review paper intends to assemble and discuss the main findings reported in the literature to date, and aims to stimulate interest and encourage further developments in this field.  相似文献   
86.
The transparent thermoluminescent aluminum oxide‐based glass of 15Al2O3–35P2O5–25CaO–25Na2CO3, abbreviated as APCN (all in mol%) doped with different concentrations of SiO2 from 0.0–500 ppm was prepared using a conventional melt‐quenching technique. The TL sensitivities of the prepared glasses were investigated at 3 Gy γ‐dose using a 60Co source and measured at a heating rate 10 C/sec. The highest TL intensity of the material doped with SiO2 was found at a concentration of 500 ppm (APCNSi5). Deconvolution of the glow curve from APCNSi5 resulted in four peaks at about 161, 194, 237 and 293 C with a Figure Of Merit (FOM) of 1.28%. The APCNSi5 specimen had the best dosimetric properties when compared with the other samples. Reproducibility, repeatability, dose–response curve and fading effect were checked for peak 3, which appeared at about 237 C. The results displayed that the APCNSi5 glass system was a low‐Z material (Zeff ≈ 10), and had good reproducibility and good repeatability. Peak 3 showed good linearity over a dose range up to 20 Gy (R2 = 0.999) and sublinearity behaviour was found. The signal from APCNSi5 faded by about 11% after 2 days post irradiation, therefore it showed almost no significant loss. Such properties make the newly prepared glasses suitable for and highly recommended for use in γ‐dosimeters. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
87.
Small animal deep‐tissue fluorescence imaging in the second Biological Window (II‐BW, 1000–1350 nm) is limited by the presence of undesirable infrared‐excited, infrared‐emitted (900–1700 nm) autofluorescence whose origin, spectral properties and dependence on strains is still unknown. In this work, the infrared autofluorescence and laser‐induced whole body heating of five different mouse strains with distinct coat colors (black, grey, agouti, white and nude) has been systematically investigated. While neither the spectral properties nor the magnitude of organ autofluorescence vary significantly between mouse strains, the coat color has been found to strongly determine both the autofluorescence intensity as well as the laser‐induced whole body heating. Results included in this work reveal mouse strain as a critical parameter that has to be seriously considered in the design and performance of small animal imaging experiments based on infrared‐emitting fluorescent markers.

  相似文献   

88.
Crop formations consist of geometrically organized regions ranging from 2 to 80 m diameter, in which the plants (primarily grain crops) are flattened in a horizontal position. Plants from crop formations display anatomical alterations which cannot be accounted for by assuming the formations are hoaxes. Near the soil surface the curved stems often form complex swirls with 'vortex' type patterns. In the present paper, evidence is presented which indicates that structural and cellular alterations take place in plants exposed within the confines of the 'circle' type formations, differences which were determined to be statistically significant when compared with control plants taken outside the formations. These transformations were manifested at the macroscopic-level as abnormal nodal swelling, gross malformations during embryogenesis. and charred epidermal tissue. Significant changes in seed germination and development were found, and at the microscopic level differences were observed in cell wall pit structures. Affected plants also have characteristics suggesting the involvement of transient high temperatures.  相似文献   
89.
Abstract

Mastoparan B (MP-B) is an antimicrobial cationic tetradecapeptide amide isolated from the venom of the hornet Vespa basalis. NMR spectroscopy was used to study the membrane associated structures of MP-B in various model membrane systems such as 120 mM DPC micelles, 200 mM SDS micelles, and 3%(w/v) DMPC/DHPC (1:2) bicelles. In all systems, MP-B has an amphiphilic α-helical structure from Lys2 to Leu14. NOESY experiments performed on MP-B in nondeuterated SDS micelles show that protons in the indole ring of Trp9 are in close contact with methylene protons of SDS micelles. T1 relaxation data and NOE data revealed that the bound form of MP-B may be dominant in SDS micelles. The interactions between MP-B and zwitterionic DPC micelles were much weaker than those between MP-B and anionic SDS micelles. By substitution of Trp9 with Ala9, the pore-forming activity of MP-B was decreased dramatically. All of these results imply that strong electrostatic interactions between the positively charged Lys residues in MP-B and the anionic phospholipid head groups must be the primary factor for MP-B binding to the cell membrane. Then, insertion of the indole ring of Trp9 into the membrane, as well as the amphiphilic α-helical structures of MP-B may allow MP-B to span the lipid bilayer through the C-terminal portion. These structural features are crucial for the potent antibiotic activities of MP-B.  相似文献   
90.
Effects of biodrying process on municipal solid waste properties   总被引:1,自引:0,他引:1  
In this paper, the effect of biodrying process on municipal solid waste (MSW) properties was studied. The results obtained indicated that after 14 d, biodrying reduced the water content of waste, allowing the production of biodried waste with a net heating value (NHV) of 16,779 ± 2,074 kJ kg−1 wet weight, i.e. 41% higher than that of untreated waste. The low moisture content of the biodried material reduced, also, the potential impacts of the waste, i.e. potential self-ignition and potential odors production. Low waste impacts suggest to landfill the biodried material obtaining energy via biogas production by waste re-moistening, i.e. bioreactor. Nevertheless, results of this work indicate that biodrying process because of the partial degradation of the organic fraction contained in the waste (losses of 290 g kg−1 VS), reduced of about 28% the total producible biogas.  相似文献   
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