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841.
农业科技成果转化的制约因素和解决对策 总被引:4,自引:0,他引:4
分析了农业科技成果转化的制约因素,提出了转变目前现状的对策。 相似文献
842.
稻米综合品质与结实期气象因子的关系研究 总被引:2,自引:0,他引:2
通过全国12个省的13个试点进行的多品种多播期试验,研究证明结实期日均温是影响稻米综合品质的主要气象因子;两者间呈二次曲线关系;结实前、中期为决定稻米综合品质优劣的温度敏感时段。 相似文献
843.
磁混肥对梨果产量品质及梨树酶活性的研究 总被引:1,自引:2,他引:1
磁混肥比混肥和习惯用肥明显增产。其中,以每株施花肥、壮果肥粪水各5kg,50kg和磁混肥1.5kg,2.3kg的产量最高,其糖/酸比值为67.3,叶片中养分N∶P_2O_5∶K_2O=1.0∶0.17∶0.60,磷含量高。日增长体积以每株施花肥、果肥粪水各25kg,50kg和磁混肥0.75kg,1.17kg处理最大,为6.06×10~(-6)mm~3。磁混肥处理SOD酶活力前期强,利于抗衰老,其后逐渐减弱,有利促进梨果成熟。 相似文献
844.
Soil phosphorus release to the water bodies in the upland fields of yellow soil areas and impacting factor was studied in Guizhou province. The results showed that the content of dissolved active P of surface runoff from various upland fields of yellow-soil were significantly different, which the concentrations of dissolved active P of runoff correlated with the contents of available-P, amorphous oxides of A1, and organic matter in the soils. The amount of soil phosphorus release to the water bodies affected by the level of applying P fertilizer and the process of corn growth, which with fertilizing from 150 to 900 kg P205 ha^-1 in the soil with high P level, the average contents of dissolved active P in the permeability-water of the soil increased from 0.020 mg L^-1 to 0.137 mg L^-1. The amount of soil phosphorus release to the water bodies also affected by environmental factor, which the amount of soil phosphorus release significantly increased under the conditions that temperature is 30℃-35℃, water/soil ratios is 15:1-25:1, submergence-time by water is 12-18 h and pH value of acid rains is 3.82-3.73. 相似文献
845.
鲜加盐白面条色泽及其影响因素的研究 总被引:2,自引:0,他引:2
研究了黑龙江省小麦品种龙麦26和龙辐麦12在四个加水量水平28%~40%下的鲜加盐白面条(FWSN)制作与色泽.结果表明,两个品种FWSN加水量在28%~32%时,亮度(L*)显著降低,黄度(b*)显著增大;加水量在32%~45%时,L*值升高,b*值降低.两个品种FWSN放置24 h后,随着加水量提高,L*值降低,红度a*值显著增加,b*值变化不大.在加水量28%,放置3 h和24 h,FWSN的L*值较高.FWSN在储藏期间色泽稳定性和保持性很关键.结果表明,两个品种放置3~72 h,FWSN的L*值显著降低.对于不同地点种植的龙麦26和龙辐麦12,蛋白质含量与FWSN的L*值显著负相关(r=-0.446,p=0.05).随着出粉率提高,FWSN的L*值显著降低.不同地点种植的龙麦26和龙辐麦12,多酚氧化酶活性对FWSN色泽影响不大. 相似文献
846.
一种分析边坡稳定性的新型方法 总被引:1,自引:0,他引:1
本文对人工神经网络即BP模型做了简要的介绍,并用BP网络的非线性映射能力计算了边坡稳定性的安全系数。结果表明利用BP网络求得的安全系数满足工程要求,并且其方法是合理、简单、可行的,值得推广。 相似文献
847.
基于青浦区推进农民居住集中工作的调查资料,分析了整个居住集中过程中农民的意愿水平、推动和制约因素政策的有效性及其相关性等因素,并针对性地提出相关的政策建议和措施。 相似文献
848.
基于"3S"的云南省石屏县土地利用动态特点分析 总被引:2,自引:0,他引:2
利用土地利用电子数据和SPOT-5卫星遥感数据,在3S技术的综合应用基础上对石屏县1992、2005年两个时期土地利用变化进行了研究。研究表明:①1992年至2005年,研究区园地变化速度较快,动态度达到了20.23%。未利用土地面积减少18865.48 hm2,耕地、林地面积分别增加了7143.22和6057.07 hm2。但由于未利用土地、耕地、林地在研究初期面总量较大,动态度较小。②在研究时段内,该区土地利用动态转化过程中以耕地、林地、未利用土地三者之间的转化、耕地、林地、未利用土地转化为园地,耕地、林地转化为居民用地及工矿等11种转化为主。③该区土地利用综合指数1992年为193.19,2005年为204.49,土地利用处于发展期,但与全国土地利用综合指数220相比有一定的差距。④农业产业结构调整、地方政府政策导向以及城镇建设用地的扩展等是影响研究区耕地变化的主要原因。 相似文献
849.
AIM: To investigate the protective role of heat-shock protein 70 (HSP70) in the pathogenesis of gastric mucosal damage in cirrhotic rats with portal hypertensive gastropathy (PHG).METHODS: The rat model of liver cirrhosis with PHG was established by injection with tetrachloride.The animals were divided into normal control group, PHG group, PHG+heat treatment group, PHG+BPI21 group and PHG+endotoxin groups.The endotoxin used in the experiment was at the dose of 3 mg/kg and endotoxin antagonist BPI21 was at the dose of 2 mg/kg.HSP70 was induced by pre-treating the animals with mild whole-body heating.The levels of HSP70 and tumor necrosis factor alpha (TNF-α) in the gastric mucosa were measured by ELISA.Furthermore, the pathological changes of the gastric mucosa were observed under microscope with HE staining.RESULTS: Compared with the normal control rats, the rats in PHG group showed obvious gastric pathological lesion, decrease in HSP70 production and increase in TNF-α level in the gastric mucosa, and increased endotoxin concentration in the plasma.Compared with PHG+endotoxin group, the gastric mucosal lesion in PHG+BPI21 group was significantly attenuated, accompanied by the increase in HSP70 production and decrease in TNF-α level in the gastric mucosa.Heat treatment increased HSP70 production and decreased TNF-α concentration in the PHG rats, thus attenuating the gastric mucosal damage.CONCLUSION: HSP70 alleviates the gastric mucosal lesion induced by endotoxin in cirrhotic rats with PHG and decreases the concentration of TNF-α in gastric mucosa, indicating a protective role of HSP70 in the pathogenesis of gastric mucosal damage in PHG. 相似文献
850.
AIM: To study the effects of basic fibroblast growth factor (bFGF) on neuronal apoptosis and fractalkine expression in ischemic penumbra after cerebral ischemia/reperfusion in rats.METHODS: Thirty-six rats were randomly divided into 3 groups: sham operation group, ischemia/reperfusion group and bFGF group. The model of middle cerebral artery occlusion was established by the method of intraluminal filament blockage. The middle cerebral arteries were blocked for 1 h and then reperfused for 24 h. Neurological performances of all rats were scored with Bederson's standard. The brain tissues of the rats were stained and the average infarct volume was calculated. TUNEL method was used to determine the number of apoptotic neurons, and the expression of fractalkine was detected by the method of immunohistochemistry.RESULTS: The score of neurological performances in bFGF group was 2.23±0.59, lower than that in ischemia/reperfusion group (3.18±0.65). The number of apoptotic neurons in bFGF group (13.22±1.35) was lower than that in ischemia/reperfusion group (17.28±1.01, P<0.05), which was the lowest in sham operation group (0.91±0.65). Compared with sham operation group, the expression of fractalkine in ischemia/reperfusion group was decreased. The expression of fractalkine in bFGF group was mainly higher than that in ischemia/reperfusion group (P<0.05).CONCLUSION: Up-regulation of fractalkine may be one of the molecular mechanisms of bFGF to protect neurons against ischemia/reperfusion injury. 相似文献