基于kn连接关系的图的着色问题与"折叠法"

引入了一类基于连接关系的图,并结合“折叠法”对该类图的着色问题与四色猜想进行了研究,给出了四色猜想的一个必要条件和一个等价命题的证明．最后提出了相关的猜想．     

喷杆式喷雾机水平折叠喷杆设计与试验

针对喷杆式喷雾机在农作物生长中后期进行施药作业时需加装吊喷杆、分禾器等施药辅助装置,而加装后立式折叠喷杆易产生干涉,甚至无法折叠等问题,设计一种基于3WF-1000型喷杆式喷雾机的宽幅水平折叠喷杆.采用解析法与遗传算法对喷杆水平展开机构及喷杆展开角速度进行优化设计,实现喷杆水平展开与折叠动作的流畅、平稳;提出一种喷杆偏...     

新型移动式折叠喷雾机的研究

设计了一种新型的小型多功能机械移动式折叠喷雾机,可以进行水平方向和垂直方向的药液喷洒,配有机械行走装置,主要用于叶面施肥、喷洒农药、洒水等,与普通的手动式喷雾机相比,具有质量轻、喷洒面积大,明显减轻劳动强度的优点.     

传统民间竹制折扇设计思想探微

折扇是传统扇子的改良型产品,既具有消暑降温、避阳取风的实用功能,也具有很高的文化价值和艺术价值,是传统民间器具中重要的一员。文中介绍了折扇的发展历史、制作工艺,从设计的角度分析了折扇的设计思想,即简洁实用的设计功能、折叠便携的设计理念和雅俗共赏的设计文化。     

《长恨歌》札记两则

白居易《长恨歌》中有两处细节值得讨论:一是"珠箔银屏迤逦开"句中的"银屏"指多扇联屏,"迤逦开"指"折叠";二是"钿合金钗寄将去"中"钿合金钗"反映了唐代上层社会流行的习俗:赠送情人以表达爱意.     

仫佬族5项舌运动类型的研究

调查了仫佬族舌运动类型（卷舌、叠舌、翻舌、尖舌、三叶舌）309例（男120例,女189例）。结果表明：5种舌运动类型出现率在性别间均无显著差异;5项舌运动类型间的相关性较小,仅有3对相关;卷舌基因与尖舌基因间存在一定的联系,翻舌基因与尖舌、三叶舌基因间存在基因互作的关系;与国内外其它群体比较,仫佬族卷舌率、翻舌率、尖舌率和三叶舌率均较低。     

TRANSCUTANEOUS ULTRASONOGRAPHIC EVALUATION OF THE AIR-FILLED EQUINE STOMACH AND DUODENUM FOLLOWING GASTROSCOPY

Gastroscopy with air insufflation was performed in 10 ponies, after which a transcutaneous ultrasound examination of the stomach and duodenum was performed immediately and at 1, 2, and 4 h postgastroscopy, and 24 h after feeding. Stomach measurements included the dorsoventral and craniocaudal dimensions, as well as the stomach depth from the skin surface and stomach wall thickness at the different time periods. Gastric wall folding was observed in one pony, becoming most distinct 2–4 h postgastroscopy. An undulating stomach wall was noted in eight other ponies postgastroscopy. These observations appeared to be a response to the deflation of the stomach as the insufflated air was released gradually. Gas was detected in the duodenum after the gastroscopy. The parameters measured were noted to be useful to evaluate the extent of stomach distension due to air or feed. The ultrasonographic appearance of the stomach can, therefore, be altered by gastroscopy and this should be borne in mind when examining horses with suspected gastric disease.     

Optimal Cleavage and Oxidative Folding of α-Conotoxin TxIB as a Therapeutic Candidate Peptide

Alpha6beta2 nicotinic acetylcholine receptors (nAChRs) are potential therapeutic targets for the treatment of several neuropsychiatric diseases, including addiction and Parkinson’s disease. Alpha-conotoxin (α-CTx) TxIB is a uniquely selective ligand, which blocks α6/α3β2β3 nAChRs only, but does not block the other subtypes. Therefore, α-CTx TxIB is a valuable therapeutic candidate peptide. Synthesizing enough α-CTx TxIB with high yield production is required for conducting wide-range testing of its potential medicinal applications. The current study optimized the cleavage of synthesized α-CTx TxIB resin-bounded peptide and folding of the cleaved linear peptide. Key parameters influencing cleavage and oxidative folding of α-CTx TxIB were examined, such as buffer, redox agents, pH, salt, co-solvent and temperature. Twelve conditions were used for cleavage optimization. Fifty-four kinds of one-step oxidative solution were used to assess their effects on each α-CTx TxIB isomers’ yield. The result indicated that co-solvent choices were particularly important. Completely oxidative folding of globular isomer was achieved when the NH₄HCO₃ or Tris-HCl folding buffer at 4 °C contained 40% of co-solvent DMSO, and GSH:GSSG (2:1) or GSH only with pH 8~8.7.     

不同砧木处理方法对3种橡胶树芽接苗生长的影响

为了缩小橡胶树芽接苗砧木芽对砧木养分的消耗,缩短接穗的待抽芽时间,减少抹芽用工,降低育苗成本,采用截砧和折砧2种砧木处理方法,对目前生产上常用的3种橡胶树芽接苗（小苗芽接袋苗、籽苗芽接袋苗、籽苗芽接杯苗）的砧木进行处理,比较分析这2种方法对橡胶树芽接苗砧木芽、接穗出芽及生长情况。结果表明：（1）折砧处理可极显著减少橡胶树芽接苗2~5次的抹芽次数及3.5~13倍的抹芽用工。（2）折砧处理可极显著提高橡胶树袋育苗10%~20%的抽芽率和成苗率,截砧处理可使籽苗芽接苗的苗木质量提高20%~45%。（3）培育橡胶树小苗芽接苗时,宜采用折砧方法处理砧木;培育籽苗芽接苗时,宜采用截砧方法处理砧木。     

可折展管道蠕动并联机构设计与运动仿真

为探索管道蠕动机构及其移动方式,设计一种具有折展能力的3-URU管道蠕动并联机构。该机构支链运动副R与U的空间位置关系能等效成Sarrus结构,可实现并联机构的折展,对折展原理和折展干涉进行分析,求得该机构折展比,并通过仿真验证其折展效果。应用螺旋理论计算该机构自由度,求解位置正解方程,并通过蒙特卡洛法求得该机构的工作空间。在管道内对机构进行蠕动步态规划,并利用ADAMS软件进行管道内的蠕动步态验证,得到两平台位移曲线和支链转角变化曲线。研究表明,该并联机构可实现管道内的蠕动,且折叠后体积较小。