城市住宅地价变化影响因素的通径分析——以石家庄为例

定量测度各影响因素对城市住宅地价的直接和间接效应对城市住宅地价的合理发展和城市土地利用与开发的宏观调控具有重要意义。论文在剖析城市地价变化影响因素的基础上,运用通径分析方法,对各影响因素与城市住宅地价之间的关系进行定量厘定,挖掘两者之间的内在联系。结果表明:1)住宅地价的变化受到经济发展水平的综合影响效应在所有影响因素中最大。经济发展水平的间接通径系数最大,表明经济发展水平主要是通过作用其他各方面因素来影响住宅地价的发展。2)从直接效应看,房地产市场状况、基础设施状况和经济发展水平对住宅地价的直接影响效应较大,从间接效应看,经济发展水平和环境质量变化对住宅地价的间接影响效应较大。3)城市规模与潜力直接通径系数和间接通径系数在各个影响因素中均最小,对住宅地价的影响较弱。     

Influence of salinity and moisture on the threshold shear velocity of saline sand in the Qarhan Desert,Qaidam Basin of China: A wind tunnel experiment

Determination of the threshold shear velocity is essential for predicting sand transport, dust release and desertification. In this study, a wind tunnel experiment was conducted to evaluate the influence of salinity and moisture on the threshold shear velocity of saline sand. Saline sand samples (mean particle size of 164.50-186.08 μm and the total silt, clay and salt content of 0.80%-8.25%) were collected from three saline sand dunes (one barchan dune and two linear dunes) in the Qarhan Desert, Qaidam Basin of China. Original saline sand samples were placed in two experimental trays for wet and dry processing to simulate deliquescence and desiccation, respectively. Surface moisture content ranging from 0.30% to 1.90% was generated by the steam method so that the saline sand can absorb water in a saturated water vapor environment. The motion of sand particles was determined by the observers with a solid laser. The laser sheet (0.80 cm thick), which was emitted by the solid laser, horizontally covered the sand surface and was bound to the sand. Results show that the cohesion of saline sand results from a combination of salt and water. The threshold shear velocity increases exponentially with the increase in crust thickness for the linear sand dunes. There is a positive linear correlation between the original moisture content and relative threshold shear velocity. The threshold shear velocity of dewatered sand is greater than that of wet sand with the same original moisture content. Our results will provide valuable information about the sand transport of highly saline soil in the desert.     

Establishment and Optimization of INH Epitope Peptide Vaccine for Detection of Antibody

In this study, an indirect ELISA method was established to detect inhibin hormone (INH) epitope peptide vaccine antibody, it would provide oretical reference for the determination of Fine-wool sheep after active immune body INH epitope peptide vaccine antibody. On the basis of the predecessors, using indirect ELISA method to determinate serum INH epitope peptide antibody levels of sheep, and through control different experimental conditions to look for the best experimental conditions. Through explorating the experimental conditions, finally, the testing experiment conditions were determined, which was blocked solution with skimmed milk powder, INH and GnIH synthetic peptides dilution degrees for 20 000 times, the optimum reaction time was 60 min, the best color action time was 15 min. In this experiment, a kind of method to detection antibody in the body after INH active immune sheep was built, it would provide a reference for future research.     

优质高产棉花新品种鲁棉1157的选育及栽培技术

介绍了鲁棉1157 的选育过程、农艺特征特性、产量、品质、抗性及栽培技术要点。     

低聚木糖和低聚壳聚糖及其复合制剂对肉鸡生产性能、免疫机能和盲肠菌群的影响

本试验旨在研究低聚木糖(XOS)和低聚壳聚糖(COS)及其复合制剂对肉鸡生产性能、免疫机能和盲肠菌群的影响。将240只1日龄爱拔益加(AA)肉鸡随机分为5组,每组6个重复,每重复8只。对照组(CON)饲喂基础日粮,其他处理组分别在基础日粮中添加100 mg/kg XOS(XOS),30 mg/kg COS(COS),50 mg/kg XOS+10 mg/kg COS(XCⅠ),75 mg/kg XOS+15 mg/kg COS(XCⅡ)。结果表明:与对照组相比,XOS、XCⅠ、XCⅡ均能显著提高肉鸡21 d、42 d平均体重(BW)和1²1 d平均日增重(ADG)(P<0.05);XCⅠ、XCⅡ较COS 42 d体重和121 d平均日增重(ADG)(P<0.05);XCⅠ、XCⅡ较COS 42 d体重和1⁴2 d的ADG显著提高(P<0.05)。与对照组相比,XCⅠ、XCⅡ14 d、28 d肉鸡胸腺指数及14 d肉鸡十二指肠和空肠黏膜IgG含量;且XCⅠ14 d肉鸡盲肠乳酸杆菌数量较CON和XOS也有提高。结果提示,XOS和COS能改善肉鸡生产性能,改善肉鸡微生物区系,提高机体免疫功能,且XOS与COS低剂量复合添加效果优于单一寡糖,两者具有协同效应,本试验条件下以50 mg/kg XOS+10 mg/kg COS复合效果为最佳。     

不同沟垄覆盖下土壤水热效应对旱作马铃薯生长及产量的影响

针对宁南山区春季降雨少、低温不利于马铃薯出苗,而作物生育中后期高温胁迫限制马铃薯块茎形成导致减产等问题,于2016年设置垄覆地膜沟内覆盖塑料地膜(DM)、玉米秸秆(JG)、生物降解膜(SM)、麻纤维地膜(MM)、液态地膜(YM)及沟不覆盖(BM),以传统平作为对照(CK),研究沟垄覆盖模式对土壤温度、土壤水分、旱作马铃薯生长及块茎产量的影响.结果表明:处理DM,SM,MM和YM马铃薯生育期耕层土壤温度表现出增温效应,而处理JG和BM表现为降温效应,其中处理DM增温效果和处理JG降温效果最佳.处理YM,JG对马铃薯生长前期保水效果较好,分别较CK显著提高13.3%,27.0%,而处理JG,DM对生育中后期的保墒效果较佳,分别较CK显著提高22.4%,13.2%.处理JG可显著促进马铃薯生长,其增产效果最为显著,DM次之,分别较CK增产47.8%,44.8%,其他处理较CK差异不具有统计学意义.可见,在宁南山区实施垄覆地膜沟覆秸秆模式可调控土壤水热环境,对旱作马铃薯生长及增产效果最佳.     

马尾藻海藻多糖生物活性研究新进展

近年来的研究表明,马尾藻中富含多种新型生物活性化合物,如海藻多酚、海藻多糖及多种硫酸多糖衍生物。在分离出的生物活性成分中,海藻多糖因其具有良好的保健作用和药用效果而备受关注。同时,有大量研究已经证明,马尾藻海藻多糖对人类疾病的预防以及恢复具有积极效果。因此,本文对近年来马尾藻海藻多糖的抗凝血、抗氧化、抗肿瘤、抗血管生成和抗炎症活性的最新进展进行了综述,以期能助推马尾藻海藻多糖的研究,并且协助填补理论研究与工业应用之间的知识鸿沟。     

玉米秸秆饲料进牧区的可行性分析

介绍了内蒙古畜牧业和草原生态现状,阐述了全区玉米秸秆生产量和饲料化利用情况,分析了玉米秸秆饲料进牧区的路径及其经济效益、生态效益、社会效益,以期为秸秆饲料进牧区提供理论依据。