Results 41 to 50 of about 31,792 (238)

From Douyin Shop to TikTok Shop: The Platformized Supply Chain, Spatialized Business Model, and Regional Partnership in Cross‐Border e‐Commerce

open access: yesPolicy &Internet, Volume 18, Issue 1, March 2026.
ABSTRACT This article investigates how TikTok Shop reproduces the e‐commerce model of Douyin Shop against a backdrop of divergent regulatory challenges and geopolitical distrust. One of the strategic changes we observe in TikTok Shop is the shift of consumer goods suppliers from local merchants to China‐based sellers.
Shuaishuai Wang, Jing Meng, Yitong Li
wiley   +1 more source

结构形态创构方法的工程应用

open access: yesJianzhu Gangjiegou Jinzhan, 2011
结构形态创构方法是一种以数值计算为基础,运用数学、力学原理来追求力学合理,形式美观的建筑结构形态的方法。主要包括以下两种方法:"改进进化论方法"是模仿自然界的进化现象,通过进行"保留、淘汰、补充"的操作使结构体逐步进化并演变成合理结构的结构形态创构方法;而"高度调整方法"是基于有限元法,通过计算应变能对曲面高度的微分,并根据应变能变化的敏感程度对曲面高度进行调整,最终得到一个结构应变能最小的合理结构形态的自由曲面结构形态创构方法。该方法简单、实用,所得到的结构不但能保证实现建筑师的设计理念 ...
崔昌禹, 姜宝石, 崔国勇
doaj  

A study of elasticity deformation of polymethylene chain(聚亚甲基链的弹性形变研究)

open access: yesZhejiang Daxue xuebao. Lixue ban, 2001
本文采用旋转异构态模型,对聚亚甲基链受到无相变的弹性形变后的热力学性质进行研究,计算出在不同形变时聚亚甲基链体系的自由能、内能等热力学函数,同时还分析了应力与弹性形变的关系以及内能对弹性形变的贡献.
JIANGZhou-ting(姜舟婷)   +2 more
doaj   +1 more source

CT imaging anatomy of myocardial bridge-mural coronary artery and its relationship with atherosclerosis [PDF]

open access: yes, 2015
研究背景:心肌桥-壁冠状动脉(MB-MCA)是一种先天性冠状动脉解剖变异,一直被认为是种良性病变。一般情况下,不引起临床症状,但可能出现心肌缺血、心律失常、心肌梗死及猝死等临床表现。明确MB-MCA的形态学特征及其与冠状动脉粥样硬化之间的关系,为相关疾病的诊断及治疗提供解剖依据。 目的:(1)应用64排多层螺旋CTA观察并测量MB-MCA发生率及其形态学特征;(2)探讨左前降支心肌桥(LAD-MB)与冠状动脉粥样硬化的关系。 实验方法:(1)回顾性分析本院2013.05-2014 ...
李菊香
core  

Electrospun Carbon Nanofiber‐Based Multifunctional Electrocatalysts for Zinc‐Air Batteries and Overall Water Splitting: Fabrication, Progress, and Perspective

open access: yesRare Metals, Volume 45, Issue 3, March 2026.
ABSTRACT The development of high‐performance and stable electrocatalysts for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) plays a critical role in advancing clean energy technologies, including metal‐air batteries and hydrogen production through overall water splitting.
Chen‐Yu Cai   +4 more
wiley   +1 more source

The cloning,expression and characterization of the Marsupenaeus japonicus ML gene (MjML) [PDF]

open access: yes, 2016
日本囊对虾(Marsupenaeusjaponicus)是我国四大养殖对虾品种之一,具有重要的经济价值。日本囊对虾幼体发育过程复杂,受精卵孵化后需要经过无节幼体,溞状幼体,糠虾幼体和仔虾4个发育阶段,发育过程中蜕皮频繁,蜕皮周期较短。近年来,随着日本囊对虾养殖规模的逐步扩大,各种细菌性疾病对其养殖业的发展造成了巨大的影响,并造成了严重的经济损失。 ML(MD-2-relatedLipid-recognition)家族为一类具有保守ML单结构域的蛋白质,能够直接和脂类结合 ...
徐伊桦
core  

Precise Tailoring of the Coordination Environment of Single‐Atom Cu(I) on Trifurcate AlL3 Supports for Click Chemistry

open access: yesRare Metals, Volume 45, Issue 3, March 2026.
ABSTRACT Single‐atom catalysis hinges on fundamental challenges in precisely controlling metal‐support interactions and rationally regulating metal–adsorbate relationships. Herein, we report a universal strategy for constructing highly efficient and well‐defined Cu(I) single‐atom catalysts based on a trifurcate AlL3 molecular support.
Donghui Zhang   +9 more
wiley   +1 more source

狮弓蛔线虫(TOXASCARISLEONINA)的形态学研究

open access: yes野生动物学报, 1989
本文对狮弓蛔虫(Toxascaris leonina)虫体及其虫卵进行了全面而系统的形态学研究。本项研究使用饱和盐水漂浮法对哈尔滨动物园猫科动物进行粪检,用盐酸左旋咪唑进行驱虫,对获得的虫体及其虫卵分别利用光学显微镜和电子显微镜进行了形态学研究。在国内首次利用电子扫描显微镜和电子透射显微镜对获得的狮弓蛔虫虫体及虫卵进行了形态学的观察。发现了一些过去未知的结构:(1)卵黄膜的超显微结构(2)细齿形态与排列方式(3)雄虫的尾感器(4)雄虫肛门前缘的乳头状突起(5)唇尖部的口孔与唇片的连接方式和部位(6 ...
车丽美   +6 more
doaj  

Long-term changes of diatom community in the frequent HAB areas of the East China Sea and the morphological response of typical species to physio-chemical variables [PDF]

open access: yes, 2016
硅藻是浮游植物的主要组成类群,与浮游植物群落演替和赤潮发生密切相关。我国长江口及临近海域近十几年来频发赤潮,其发生机制比较复杂,为了探讨硅藻长周期变化与赤潮发生的关系,本研究于2002年至2013年间,通过藻华973航次在长江口及临近海域典型赤潮高发区分别进行19个航次的浮游植物拖网和水样采集,共获得浮游植物样品3417个,进行了硅藻种类组成与数量分析,研究了其年际变化、季节变化和地理分布及其受控因素。 一般情况下,浮游植物群落中硅藻在种类和数量上都占优势地位 ...
刘昱涵
core  

Nanofiltration Membranes for High‐Selectivity Separation of Li+ and Mg2+ From Salt Lake Brines: Strategies, Challenges, and Perspectives

open access: yesRare Metals, Volume 45, Issue 3, March 2026.
ABSTRACT Against the backdrop of global clean energy transition and surging demand for lithium resources, lithium extraction from salt lakes presents unprecedented development opportunities. Nanofiltration (NF) membrane technology, recognized for its efficiency, energy savings, and environmental benefits, demonstrates significant application potential ...
Wen‐Feng Li   +5 more
wiley   +1 more source

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