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991.
n this paper,researches of digital valves in Japan in recent years are briefly de-scribed. The operation principles and the structure of a new digital speed control valve are analysed.This new valve is made by Japanese Tokyokeiki company. Based on these investigations , theoretiealanalysis,degital simulation and experimental study are emphasized to the valve's static and dynamiccharacteristics. 相似文献
992.
The hydraulic loading and wet/dry(W/D) ratio,which are two important indexes in the constructed rapid infiltration,can affect the removal effect.Presently,the domestic experimental reports about the hydraulic loading and(W/D) ratio aiming at the Three-Gorges Reservoir Region is rather scarce.This article studies some pertinent hydraulic loadings and W/D ratios suitable for the Region.The authors emphatically research the effect of CRI treating COD,TN and TP in the sewage under four hydraulic loadings and three different W/D ratios.It is suggested that when the temperature is ascending,the W/D ratio can be risen to some extent.The variations of loading and ratio can affect the COD,TP removal effect a little,but affect the TN removal effect much.The experimental conclusions can provide evidence to the application of constructed rapid infiltration in the Three-Gorges Reservoir Region. 相似文献
993.
Establishing and Application of the Mathematical Model of the Impulse Electroflotation Reacting Tank
The properties of the Impulse electroflotation equipment are introduced briefly ,and the factors that influence the treatment effect of Impulse electroflotation are analyzed. The mathematical model of the Impulse electroflotation reacting tank which determines the height, volume and treatment capability of Impulse electroflotation is provided on the base of the basic equations of electroflotation. A calculate software for the design of Impulse electroflotation reacting tank is developed and the source code is given. 相似文献
994.
应用IBD快速检测试纸和琼脂凝胶免疫扩散试验(AGIDT),对不同疫苗免疫鸡检测结果均为阴性,对人工感染强毒鸡最早检出IBDV的时间,试纸检测法为感染后36h,琼脂扩散检测法为感染后96h。试纸检出的最低含毒量为800ELD50,ELISA检出的最低含毒量为400ELD50,琼扩检出的最低含毒量为2 5×104ELD50,试纸检出的敏感性比琼扩提高32~64倍。IBD试纸检测简便、快速、敏感、特异,是诊断鸡法氏囊病的有效方法。 相似文献
995.
Summary A rapid fluorescent in situ hybridization protocol, which can be completed in one working day, has been utilised to visualize chromosome preparations of barley, chickpea, white clover, millet, rye, sugarcane, wheat, Aegilops spp. and Leymus spp. Both total genomic DNA and cloned nuclear rDNA were used as a probe. This protocol has the advantage of brevity and flexibility over more conventional approaches, and has made fluorescent in situ hybridization a routine cytological procedure. 相似文献
996.
This paper describes a PC controlled brake valve automatic testing system which uses industrial control(computer) and Advantech powerful date acquition card PCI-1710L,and chooses Advantech PCI-1730 as the I/O card,(uses) FUJI servo systrm as the transmission mechanism.The system monitor the brake valve's quality based on analyseing the static characteristics of the brake valve.The authors also introduce the principle and structure of the system,hardware and software design process.The system works well in practice. 相似文献
997.
Summary Sixty-six chrysanthemum (Dendranthema grandiflora) inbred selections, noninbred cultivars and hybrids, and D. makinoi were the base populations from which up to three generations of inbreds were obtained using multiple plant descent. Each parent possessed pseudo-self compatibility (PSC), which allowed seed set following self pollination. Rapid-generation cycling (laboratory seed ripening to heart stage and subsequent embryo rescue) reduced generation time and minimized confounding maternal with zygotic inbreeding depression during post heart-stage seed development. Selection criteria were male/female fertility and PSC. Two stages of the life cycle were chosen to evaluate inbreeding depression: germination (seed development to germination) and survivorship (fertile individuals at anthesis). PSC was environmentally interactive and genotype dependent, causing variable levels of self seed set between and within populations and generations. By the end of the second generation, families from all noninbred cultivars, D. makinoi, and one F1 hybrid were eliminated from the experiment due to self incompatibility and/or inbreeding depression. Post-germination inbreeding depression was severe in several advanced inbreds. Inbred progeny of most F1 or F2 hybrids expressed less or equal amounts of inbreeding depression compared to advanced inbreds. Linear regression coefficients for either germination or survivorship on percent homozygosity were negative. Correlation coefficients between percent germination and survivorship (as a percent of seed set) were highly significant for Minnesota inbreds (r=0.67, P0.002) and hybrids (r=0.67, P0.006). The correlation coefficient was higher when percent germination and survivorship (as a percent of germinated seedlings) were compared (r=0.95, P0.001).Abbreviations F
Fisher's Coefficient of Inbreeding
- IBD
Inbreeding Depression
- PSC
Pseudo-self Compatibility
- RGC
Rapid Generation Cycle
- SI
Self Incompatibility 相似文献
998.
The authors introduce the applied issue of optics navigation in systems new traffic method,Bus Rapid Transit-BRT.They apply Hough switch to dispose sampling image,through the road tracking system navigation emulate educed instantaneous road curve function,and provides vehicles instantaneous road information.By using error feedback control to control vehicles' orient, they put forward the concretely application method of the optics navigation technique in BRT. 相似文献
999.
Summary The male sterility system MS-1 of Brassica oleracea was studied in order to elucidate if nucleo-cytoplasmic interactions determine this system. Crosses of male sterile MS-1 genotypes with heterozygous MS-5 genotypes gave fully fertile F1 progenies. Selfing of seven F1 plants resulted in five F2 populations showing a 9:7 segregation ratio and two a 3:1 ratio for fertile and male sterile plants. Two F2 progenies deviated from the expected 9:7 or 3:1 segregation ratios for fertile and male sterile plants. Thermosensitivity and distortion of the meiosis are suggested as the causal factors underlying the deviation of the segregation ratios. It was concluded that nuclear factors determine the male sterility in the MS-1 system, because the presence of a nucleocytoplasmic interaction in this system should have given only a 3:1 segregation ratio for fertile and male sterile plants in the F2 generation. 相似文献
1000.