Climate change record in subsurface temperatures: A global perspective

Analyses of underground temperature measurements from 358 boreholes in eastern North America, central Europe, southern Africa, and Australia indicate that, in the 20th century, the average surface temperature of Earth has increased by about 0.5 degreesC and that the 20th century has been the warmest of the past five centuries. The subsurface temperatures also indicate that Earth's mean surface temperature has increased by about 1.0 degreesC over the past five centuries. The geothermal data offer an independent confirmation of the unusual character of 20th-century climate that has emerged from recent multiproxy studies.     

朱鹮消化系统的组织学观察

对一只意外死亡朱的消化系统各器官进行组织学观察,结果发现：消化管均具有一般的四层结构,但食管粘膜内有密集的泡状腺,分泌物丰富;腺胃和肌胃均未见粘膜肌,但肌层很发达;小肠绒毛较长,未见中央乳糜管构造,固有膜及绒毛内有丰富的平滑肌束;盲肠亦有短的绒毛,且淋巴组织发达,可形成淋巴小结。肝小叶间结缔组织少,小叶界线不清。     

品种对3∶1式移栽棉棉铃发育的影响

研究结果表明：品种对铃重影响作用表现为中早熟品种大于中熟品种,品种间差异随育苗期延后而增大。中早熟品种棉纤维发育早于中熟品种。品种对棉籽（仁）脂肪累积作用表现为中早熟品种优于中熟品种,而蛋白质累积则相反。棉仁棕榈酸、油酸、硬脂酸含量变化品种间差异较小,豆蔻酸和亚油酸变化趋势相反,品种间存在差异;品种对棉仁氨基酸累积的作用表现为中熟品种优于中早熟品种。３∶１式移栽棉品种选择受育苗期影响很大,早育苗时可选用中熟品种。     

嘉兴市农田种植结构调整和减灾防灾技术

阐述了嘉兴市农作物受灾现状及特点,提出了产需平衡与农田种植结构调整,农作物减灾防灾农艺技术对策等减灾防灾措施.     

春小麦受精过程及其各阶段持续时间的研究

本文对三个不同品种的春小麦的受精过程及其各阶段持续的时间进行了研究,其结果如下:1.授粉后1小时,花粉管破坏一个助细胞将精核释放于卵细胞与极核之间。2.授粉后1.5小时,精核进入卵细胞,精核在卵细胞的细胞质里有不同的取向。授粉后2小时,精核附在卵核的核膜上。3.授粉后2.5小时,精核进入卵细胞核,精核的染色质逐渐松解。授     

棉花产量结构模式的研究及其在育种上应用的意义

本文是应用多元回归分析方法,研究两个棉花有限总体的三个产量结构模式。分析结果表明,这三个模式是符合棉花本身实际情况的;在构成产量的诸因素中,以铃数所起的作用最大,其次为单铃重和衣份率;在高产育种工作中,应把选择重点放在铃数上,但由于铃数、铃重和衣份率之间存在着明显的负相关关系,故对铃数的选择必须有适当尺度,至     

Changes in Retrogradation Properties of Rice Starches with Amylose Content and Molecular Properties

The increases in storage modulus (G′), retrogradation enthalpy change (ΔH) and ΔH‐related Avrami kinetic parameters of gelatinized rice starch dispersions at 25% (w/w) were investigated with respect to storage period, amylose content (AC), and molecular properties. Three high‐AC and five low‐AC rice cultivars were compared for understanding the multiple influences of AC and molecular properties involved. After refining the results of correlation analysis, the G′ of just‐cooled samples changed positively, mainly with AC and additionally with the average chain length of amylose (CL_AM) and the weight ratio of extra‐long plus long chains to short chains of amylopectin (AP) (r_APchain). The developed ΔH on short‐term storage (10 days) elevated with increasing AC and CL_AM and decreasing degree of polymerization of AP (DP_AP), but after long‐term aging for one to three months with increasing r_APchain, especially for the low‐AC cultivars examined. Greater Avrami rate constants for retrogradation could be attributed to the combination of a lower DP_AP and r_APchain or AP chain length and a greater CL_AM. The polynomials using these critical factors to describe the retrogradation parameters were elucidated and could account for 85–99.6% of data deviations.     

进口盆景截获克鲁克剑线虫

对进口香港盆景检疫中发现的剑线虫进行的研究,记述了我国线虫新记录种克鲁克剑线虫Ｘｉｐｈｉｎｅｍａｋｒｕｇｉ,对剑属线虫的检疫及鉴定方法进行了总结和研讨。     

日本松干蚧检疫技术

日本松干蚧是重要的检疫害虫,通过划分疫区,进行产地检验和调运检验检疫措施来控制人为扩散蔓延,可采用直接检验法和性激素诱捕法技术进行检验,根据生物学特性、主要形态特征和用雌性激素生测法来鉴定松干蚧的种类,查出松干蚧并经检疫处理合格后方可调运。     

世界木材生产机械研究现状与发展趋势

介绍了当前世界木材生产机械研究和发展现状,分析了90年代木材生产机械的发展特点,指出了今后木材生产机械研究和发展趋势.