全文获取类型
收费全文 | 102篇 |
免费 | 0篇 |
国内免费 | 1篇 |
专业分类
化学工业 | 8篇 |
机械仪表 | 1篇 |
能源动力 | 1篇 |
轻工业 | 20篇 |
无线电 | 2篇 |
一般工业技术 | 29篇 |
冶金工业 | 31篇 |
原子能技术 | 8篇 |
自动化技术 | 3篇 |
出版年
2021年 | 2篇 |
2020年 | 1篇 |
2016年 | 2篇 |
2014年 | 2篇 |
2013年 | 1篇 |
2012年 | 1篇 |
2011年 | 4篇 |
2010年 | 3篇 |
2009年 | 1篇 |
2008年 | 3篇 |
2007年 | 1篇 |
2006年 | 1篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 2篇 |
2002年 | 1篇 |
2001年 | 1篇 |
1999年 | 4篇 |
1998年 | 5篇 |
1997年 | 5篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 4篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1990年 | 6篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 4篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 9篇 |
1976年 | 3篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1970年 | 1篇 |
1962年 | 1篇 |
1961年 | 1篇 |
1960年 | 1篇 |
1959年 | 1篇 |
1956年 | 1篇 |
1955年 | 1篇 |
1938年 | 1篇 |
1932年 | 1篇 |
排序方式: 共有103条查询结果,搜索用时 15 毫秒
11.
Friedrich Kiermeier und Gertraud Behringer 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1977,164(4):283-285
Zusammenfassung Aus der Literatur ergaben sich zahlreiche Widersprüche über die Aflatoxin-Bildung bei Temperaturen unter 10° C. Aus diesem Grunde wurden Versuche mit Pasten aus Milch- und Käsepulver angesetzt, künstlich mitAspergillus parasiticus kontaminiert und bei 1° C, 5° C und 10° C bis zu 28 Tagen bei einer relativen Luftfeuchtigkeit von 90 bis 95% gelagert. Es konnten selbst bei 1° C die Aflatoxine B1, B2, G1, G2 und M1 quantitativ bestimmt werden. Die Höhe des Milchzucker-Gehaltes hat keinen deutlichen Einfluß auf die Höhe der Aflatoxinwerte. Auch die Lagerung der Käse (Camembert und Quark) in 10%iger Salzlake hat die Aflatoxinbildung bei 20° C nicht beeinträchtigt.
43. Mitteilung: Zur Aflatoxinbildung in Milch und Milchprodukten 相似文献
Influence of cooling temperatures on aflatoxfin formation in milk products
Summary In the literature several contradictionary results have been published on the aflatoxin formation at temperatures below 10° C. Therefore experiments with pastes made from milk and cheese powder artificially cantaminated withAspergillus parasiticus, were performed at temperatures of 1° C, 5° C, and 10° C for 28 days at a relative humiditiy of 90–95%. Even at 1° C, the aflatoxins 131, B2, G1, G2, and M1 could be determined quantitatively. The lactose content did not have a significant influence on the aflatoxin values. Even storage of cheese (camembert and cottage cheese) in a 10% salt solution did not inhibit aflatoxin formation at 20° C.
43. Mitteilung: Zur Aflatoxinbildung in Milch und Milchprodukten 相似文献
12.
M Wakamiya EA Lindsay JA Rivera-Pérez A Baldini RR Behringer 《Canadian Metallurgical Quarterly》1998,7(12):1835-1840
Gscl encodes a Goosecoid-related homeodomain protein that is expressed during mouse embryogenesis. In situ hybridization and immunohistochemistry studies show that Gscl is expressed in the pons region of the developing central nervous system and primordial germ cells. Gscl expression is also detected in a subset of adult tissues, including brain, eye, thymus, thyroid region, stomach, bladder and testis. Gscl is located within a region of the mouse genome that is syntenic with the region commonly deleted in DiGeorge and velocardiofacial syndrome (DGS/VCFS) patients. DGS/VCFS patients have craniofacial abnormalities, cardiac outflow defects and hypoplasia of the parathyroid gland and thymus due to haploinsufficiency of a gene or genes located within the deleted region. Thus, the genomic location of Gscl and its expression in a subset of the tissues affected in DGS/VCFS patients suggest that Gscl may contribute to the pathogenesis of DGS/VCFS. To determine the role of Gscl during mouse embryogenesis and in DGS/VCFS, we have deleted Gscl by gene targeting in mouse embryonic stem cells. Both Gscl heterozygous and Gscl null mice were normal and fertile, suggesting that Gscl is not a major factor in DGS/VCFS. Interestingly, expression of the adjacent Es2 gene in the pons region of Gscl null fetuses was absent, suggesting that mutations within the DGS/VCFS region can influence expression of adjacent genes. In addition, embryos that lacked both Gscl and the related Gsc gene appeared normal. These studies represent the first functional analysis of a DGS/VCFS candidate gene in vivo. These Gscl null mice will be an important genetic resource for crosses with other mouse models of the DGS/VCFS. 相似文献
13.
Practical application of the zero-crossing correlation method for measuring slightly-subcritical reactivities in a swimming-pool reactor required the use of detector locations in the reflector zone near to the core boundary. Experimental investigations of neutron-noise cross-power spectra showed significant deviations from the point-reactor model at higher frequencies (> 100 Hz). Nevertheless, the use of the point-reactor model was found to be a useful approach in the analysis of the zero-crossing correlation method, yielding results which agreed well with those obtained from the rod-drop method. The theoretical part of the work is concerned with a space-dependent model calculation in two-group diffusion theory to support the experimental findings. The model calculation can explain the trends observed in the neutron-noise spectra as well as the applicability of the point-reactor model to the zero-crossing correlation method. To obtain better insight, the calculations have been extended to neutron-noise spectra when one or both detectors are located in the core zone. In the case of a large core and widely-spaced detectors, with at least one detector in the core zone, a sink frequency appears in the spectra. This effect is well known in coupled-core kinetics. 相似文献
14.
Dennis Hoch Mehdi Azimian André Baumann Jens Behringer Jennifer Niessner 《化学工程与技术》2020,43(12):2538-2547
Aerosols represent a health risk since small droplets may enter the respiratory system and cause lung cancer, allergies, or diseases like COVID-19. In this work, an Eulerian-Lagrangian computational fluid dynamics model is used based on a voxel-based (GeoDict) and a mesh-based (StarCCM+) code. For evaluating accuracy and computational time of both models, fractional filtration efficiency and pressure drop are compared to an empirical solution for a single fiber and to experimental results for a complex 3D fibrous filter material. Simulation results of both methods are in good agreement with empirical and measurement results although the complex geometry of the fibers is captured more accurately by the unstructured mesh using the same resolution. Computing times are much faster using the voxel-based code. 相似文献
15.
Lim1 is a homeobox gene expressed in the organizer region of mouse embryos. To investigate the role of Lim1 during embryogenesis, a targeted deletion of the Lim1 gene was generated in embryonic stem cells. Embryos homozygous for the null allele lacked anterior head structures but the remaining body axis developed normally. A partial secondary axis developed anteriorly in some mutant embryos. Lim1 is thus an essential regulator of the vertebrate head organizer. 相似文献
16.
17.
18.
We study the temperature-equilibration process of fluids at constant volume in a thermal conductivity cell, where an initial temperature gradient relaxes to zero. The calculation is performed in the linear approximation for a pure fluid and a binary mixture. Near the critical point of the pure fluid, the adiabatic heating process, which takes place at constant volumeV, causes equilibration to proceed four times faster whenC
P
/C
V
1 than for the process at constant pressureP. For the mixtures, the relaxation rate enhancement at constantV compared with constantP is restricted to a temperature region where the coupling between temperature and mass diffusion is small. The predictions are compared with experimental results for3He and for two3He-4He mixtures along their critical isochores. Finally, we discuss the thermal relaxation in the two-phase (liquid-gas) and one-phase (gas) regimes at the critical density, as measured with a conductivity and a calorimetry cell. The contrasting behavior for3He and a3He-4He mixture in these two regimes and under these different constraints is pointed out and discussed. 相似文献
19.
R. P. Behringer 《Journal of Low Temperature Physics》1990,81(1-2):1-17
The response of a layer of superfluid mixture to an ac heat source,Q(t)=Q
0
exp(it), is determined. In the low-frequency regime, the temperature response at the heated side of a superfluid layer is essentially identical to that of an ordinary fluid having a thermal conductivity eff and a thermal diffusion coefficient
0
/2. Here eff is the effective conductivity of Khalatnikov, and
0
is the diffusion coefficient of Griffin. At much higher frequencies, the results are more complicated. The low-frequency regime is defined in terms of the second sound velocityu
2
by u
2
2
/
0
. The ac response function is valuable in a number of ways. It can be used to obtain the system response to more complicated time-dependent variations inQ such as step changes inQ. A knowledge of the response function in the low-frequency regime provides a mechanism for directly determining the Kapitza resistance in mixtures. Finally, a knowledge of the response function provides an additional opportunity to test two-fluid hydrodynamics. Alternative tests of superfluid hydrodynamics are of particular interest in light of recent experiments that show anomalous values for eff in the low
3
He concentration limit 相似文献
20.
R. P. Behringer 《Journal of Low Temperature Physics》1986,62(1-2):15-26
The superfluid hydrodynamics of heat flow is examined for very small mass concentrationsc of3He in4He in an effort to better understand recent results for the effective heat conductivity eff, which appear to be in conflict with predictions. The full hydrodynamics contains a thermal boundary layer; within this layer the temperature and concentration gradients differ from those in the bulk fluid. An examination of finite heating effects based on the ansatz eff c
–p
for smallc shows distinctly different behavior for experimental determinations of eff whenp<1,p=1, andp>1. Thus, finite heating can be used as a probe to evaluate the exponentp. 相似文献