液压式核桃采摘机的设计与试验研究

针对传统的树冠较大、树干直径较粗的核桃树人工采摘劳动强度大、成产效率低等问题,设计了一种液压式核桃采摘机,实现了由液压系统控制偏心振动装置来完成核桃的采摘作业。试验表明:所研制的液压式核桃采摘机具有结构简单、操作简便、工作平稳安全、采净率高且无伤树体等特点,达到了预期效果。     

饲料非营养性添加物生物学作用和有效利用技术的研究

以蛋鸡、肉仔鸡、仔猪为对象 ,探讨了饲料非营养性添加物 (微生物植酸酶、寡糖、药物添加剂、香味剂、着色剂等 )对营养物质利用、生理生化指标影响的机制。并对其利用技术问题进行了研究 ,取得了一些成果     

黄河三角洲土壤含水量状况的高光谱估测与遥感反演

为探讨利用近地高光谱和遥感影像数据结合预测土壤含水量的可行方法,以黄河三角洲垦利县为研究区,采用中心波长反射率和波段平均反射率两种拟合方法,利用室外实测高光谱窄波段反射率数据模拟Land Sat8卫星宽波段反射率,进而通过组合,选取敏感光谱参量,应用多元逐步线性回归方法分别建立土壤含水量高光谱单一形式波段组合与多形式波段组合估测模型,并选取最优估测模型。采用线性混合像元分解处理遥感影像,同时采用比值均值订正方法对遥感影像反射率进行订正,在此基础上,将模型应用到经过订正的Land Sat8卫星影像,实现了对研究区土壤含水量的遥感反演。结果表明,最佳模型是基于波段平均反射率拟合方法建立的多形式波段组合估测模型。从反演结果看较为符合研究区土壤含水量的实际状况。     

Physicochemical changes and mechanism of heat-induced gelation of arrowtooth flounder myosin

Physicochemical changes of myosin during heating were investigated to elucidate the mechanism of heat-induced gelation of arrowtooth flounder (ATF) myosin at high ionic strength. Changes in dynamic properties indicated ATF myosin formed a gel in three different stages as shown by the first increase in G' (storage modulus) at 28 degrees C, followed by the decrease at 35 degrees C and the second increase at 42 degrees C. DSC thermogram showed the onset of myosin denaturation at 25 degrees C with two maximum transition temperatures at 30 and 36 degrees C. The decrease in alpha-helical content indicated ATF myosin began to unfold at 15 degrees C and the unfolding continued until it reached 65 degrees C. Turbidity measurement showed myosin began to aggregate at 23 degrees C and the aggregation was complete at 40 degrees C. Surface hydrophobicity increased consistently in the temperature range studied, 20-65 degrees C. Sulfhydryl contents decreased significantly at 20-30 degrees C due to the formation of disulfide linkages but remained constant at temperatures >30 degrees C. ATF myosin was shown to be extremely sensitive to heat, resulting in denaturation at lower temperature than other fish myosin. Denaturation was initiated by unfolding of the alpha-helical region in myosin followed by exposure of hydrophobic and sulfhydryl residues, which are subsequently involved in aggregation and gelation processes.     

基于土地利用功能测度的"三生"空间识别与优化调控

三生空间的科学划分是国土空间规划与治理体系的基础，而划分的关键在于定量识别与测度土地利用功能。该研究基于土地利用多功能价值评估方法体系，提出"三生"空间表达模式，并以张家口市为例进行"三生"空间识别与分区调控。结果表明：1）张家口市"三生"空间共涵盖9种功能组合模式，其中生态-生产-生活均衡空间比例最大，且超过80%的空间存在三重功能；2）张家口市不同功能组合模式在空间分布上呈现"局部集聚，全局分散"特征。生产功能主导空间与生活功能主导空间主要分布在洋河、桑干河和壶流河谷地，而生态功能主导空间则主要分布于东部的燕山余脉和南部太行山脉附近；3）张家口市"三生"空间优化分区可划为5种类型，生产和生活功能为主的空间分区要在强化主导功能的基础上，实现"三生"功能的协调发展，而生态功能为主的空间分区则以生态保育为首要目标。     

In vitro tetraploid induction via colchicine treatment from diploid somatic embryos in grapevine (Vitis vinifera L.)

A protocol for in vitro induction of tetraploids via colchicine-treated somatic embryos from immature zygotic embryos of diploid grapevine (Vitis vinifera L.) is reported. Embryogenic callus was initiated from immature zygotic embryos cultured on Nitsch and Nitsch (NN) medium supplemented with 1.0 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D). The callus was transferred to NN medium containing 1.0 mg/l α-naphthalene acetic acid (NAA) and 0.5 mg/l benzyladenine (BA) to establish somatic embryogenesis. The vigorously growing globular embryos were selected and treated by 0, 10 or 20 mg/l colchicine for 1, 2 or 3 days, and then immediately transferred to NN medium supplemented with 0.03 mg/l NAA and 0.5 mg/l BA, for somatic embryo conversion and plant regeneration. The number of surviving embryos and regenerated plantlets following colchicine treatment decreased with increasing colchicine concentration and treatment time. Among 29 randomly investigated plantlets regenerated from colchicine-treated somatic embryos, five solid tetraploids (2n = 4× = 76) were identified by chromosome counting analysis; all others were diploid (2n = 2× = 38). Ploidy level of plant regenerated was also determined from leaves using flow cytometry. No chimeras with both 2C and 4C nuclei was produced from colchicine-treated somatic embryos. Significant differences in leaf stomata parameters were observed between diploid and induced tetraploid plantlets.     

山羊乳腺上皮细胞的光镜观察

采用电穿孔转化法,将EGFP(增强型绿色荧光蛋白)基因转化体外培养的山羊乳腺上皮细胞。细胞穿孔转化7d后在荧光显微镜下观察。结果显示,EGFP基因成功地转入体外培养的山羊乳腺上皮细胞,EGFP基因获得表达,6种电穿孔参数的转化效果基本相同。     

Genetic diversity of European spelt wheat (Triticum aestivum ssp. spelta L. em. Thell.) revealed by glutenin subunit variations at the Glu-1 and Glu-3 loci

Summary High and low molecular weight glutenin subunit (HMW-GS and LMW-GS) compositions of 270 European spelts, 15 Iranian spelts and 25 bread wheat cultivars were analyzed by one- and two-dimensional gel electrophoresis. The results revealed a total of 22 HMW-GS alleles (4 at Glu-A1, 11 at Glu-B1 and 7 at Glu-D1) and 32 allele combinations among the three Glu-1 loci. Two major genotypes of HMW-GS: 1, 13+16, 2+12 and 1, 6.1+22.1, 2+12 were found to occur in Central European spelt wheat cultivars and landraces at higher frequencies of 35 and 28%, respectively. The Glu-B1 locus displayed the greatest variation and genetic diversity index (H) was 0.69 whereas Glu-A1 and Glu-D1 showed H index values of 0.26 and 0.19, respectively. The dendrogram constructed by HMW and LMW glutenin subunit bands revealed that European spelts form a separated cluster from common wheat suggesting that spelt and common wheat form distinct groups. In addition, all 15 Iranian spelt land variety accessions differed from European spelts and possessed similar HMW-GS alleles to common wheat. Because of a wider polymorphism Central European spelt wheats are an important genetic reserviour for improving common wheat quality. Both authors contributed equally to this work     

三氯乙酸在土壤及小麦、玉米植株中的残留动态研究

本研究通过大量的田间试验和盆栽试验,对不同时期土壤和植株中三氯乙酸残留动态进行了观察,发现在试验条件下三氯乙酸在田间土壤中最长可持留7个月;在作物的整个生长期中,以三叶期植株中三氯乙酸检出量最高,随生长期的延长,植株中三氯乙酸检出量迅速减少,但最终仍可从成熟的籽实中检出微量三氯乙酸.本文阐述了影响作物对三氯乙酸吸收的若干因素,并对土壤中三氯乙酸残留量与植株中三氯乙酸检出量的关系进行了简单的数学处理,可供有关人员在研究土壤中农药及其它有机污染物对农作物毒害问题时参考.