Results 21 to 30 of about 5,722 (111)
Zhejiang Daxue xuebao. Lixue ban, 2007 研究制备了Ni-Cu/SiO2双功能催化剂，并在离子液体和有机溶剂介质中研究柠檬醛催化加氢合成薄荷醇反应.结果表明：离子液体中催化剂对柠檬醛分子中的2位C=C双键加氢更容易，提高了催化剂选择性，反应条件更为温和；特别是可调节酸度的[bmim][AlmCln]离子液体，在竞争性加氢中促进了柠檬醛向生成薄荷醇的方向转化；在2 MPa，80 ℃的反应条件下，柠檬醛转化率为100%，对薄荷醇的选择性为88.6%.而且，催化剂和离子液体可回收和重复使用.
NIANBao-yi(念保义) +3 more
doaj +1 more source
Guangtongxin yanjiu, 2008 文章提出一种利用硅树脂调节光子晶体光子带隙的方法,光子晶体波导是通过往二维正方形光子晶体的介质柱之间填充硅树脂得到的,利用温度场改变硅树脂的折射率。数值模拟结果表明:通过温度场可对这种光子晶体的禁带结构进行调节。这种可调光子晶体可应用于制作新颖的偏光片和光开关。
谭春华, 黄旭光
doaj
New Directions for Child and Adolescent Development, Volume 2026, Issue 1, 2026.Background Working memory updating is crucial in bilingual children′s second language (L2) reading comprehension. A robust updating ability is a cognitive key for children to successfully master L2 reading comprehension. Objective This study is aimed at investigating the effect of updating ability on the L2 Chinese reading comprehension among Uyghur ...
Guangxin Li +3 more
wiley +1 more source
野生动物学报, 2013 2011年1～5月,对徐州睢宁养殖场的10只黑天鹅雏鸟的体重、体长、尾长、嘴峰、嘴裂及跗跖等外部特征和体温进行测定,运用Logistic生长曲线进行回归分析。其生长曲线均呈"S"型,显示出雏鸟外部体征发育呈现一定的顺序,符合重要功能优先发育的原则。（1）1～5日龄,雏鸟的体重呈下降趋势;雏鸟的嘴峰、跗跖基本不生长;体温升高迅速但体温调节能力还未健全。（2）6～30日龄,雏鸟体重开始增长;嘴峰生长迅速;体温逐渐上升,体温调节能力迅速增强。（3）31～90日龄,体重迅速增长;跗跖生长迅速,体温逐渐达到恒定。（
孙伟东 +4 more
doaj
Integrative Conservation, Volume 4, Issue 4, Page 652-664, December 2025.We profiled nutritional and physiological markers in captive sifakas, endangered primates from Madagascar, managed in expansive, non‐native forest enclosures. Variation in many markers reflects freely foraged diets and the energy required to maintain homeostasis under more naturalistic conditions.
Lydia K. Greene +5 more
wiley +1 more source
Integrative Conservation, Volume 4, Issue 3, Page 430-441, September 2025.Our study identifies southern China, including mountainous regions and islands, as key areas rich in phylogenetic diversity, and phylogenetic endemism of lizards that are currently under‐protected. Current protected areas however do not adequately cover regions that are critical for preserving the evolutionary history of lizards.
Tao Liang (梁涛) +8 more
wiley +1 more source
Zhongguo shiyan zhenduanxue, 2015 目的探讨全身麻醉下吸烟病人体温与体温调节性周围血管收缩反应的变化。方法全身麻醉下行择期开腹手术的成年男性病人23例(ASA1-2级),分为吸烟组(S组,n=12)与对照组(C组,n=11)。S组患者烟龄13.58±8.38年、吸烟量17.08±5.82支/日,C组患者无吸烟史,其他情况同S组;两组麻醉诱导相同,即用丙泊酚1-2mg/kg、芬太尼4μg/kg、维库溴铵0.1mg/kg,气管插管后行间歇正压通气(IPPV),维持PETCO235-40mmHg,麻醉维持用1-2%异氟烷,0.08-0.12μg/
王明玲, 郑利民, 王焱林, 黄飞
doaj
New Phytologist, Volume 247, Issue 3, Page 1117-1128, August 2025.Summary Environmental changes and their effects are among the most pressing topics of today's ecological research. Shrublands, although widespread across the globe, remain understudied in this respect. We conducted a global meta‐analysis of 81 shrubland sites subjected to experimental warming, shifts in precipitation (e.g.
Daijun Liu +11 more
wiley +1 more source
Gaoya dianqi, 2015 传统交流温升试验电源系统采用电网直接供电,因此只能进行50 Hz温升试验,而无法实施60 Hz温升试验,同时,由于其自动化程度较低,在电网电压波动以及负载随温度变化的情况下,只能通过现场手动调节调压器实现电流的稳定控制,且缺乏有效的远程监控手段,不利于系统运行的综合管理。为解决上述问题,笔者结合温升试验的工艺要求以及试验室的具体试验条件,采用发电机作为温升试验电源,通过调节变频器的输出频率改变拖动电动机的转速,实现了试品对不同试验频率的需求;采用可编程控制器设计了一套温升试验自动控制系统 ...
贾一凡 +6 more
doaj
Heart rate variability in horses with and without severe equine asthma
Equine Veterinary Journal, Volume 57, Issue 3, Page 611-618, May 2025.Abstract Background Equine asthma in severe form (severe equine asthma [sEA]) shares remarkable similarities with human asthma. Human studies detected changes in the autonomic nervous system function in asthmatic patients based on heart rate variability (HRV) analysis. Study design Observational study. Objectives To investigate the relationship between
Zsófia Nyerges‐Bohák +5 more
wiley +1 more source