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基于响应曲面的树枝粉碎装置设计与试验

农机化研究 2023年第1期45卷 168-175页

作者：王珊郑欣敦刘洪萍乔停蔡端党革荣张金发西北农林科技大学机械与电子工程学院陕西杨凌712100 扶风永恒农牧机械制造有限责任公司陕西扶风722200

针对树枝粉碎机粉碎效果差、功耗大等问题,设计了一种树枝粉碎装置,可通过喂料机构对树枝的强制性喂入,鼓式刀辊与定刀对树枝的连续切削,实现树枝的均匀连续粉碎。首先,设计了各关键部件结构参数;其次,基于树枝粉碎过程的动力学分析,分... 详细信息

针对树枝粉碎机粉碎效果差、功耗大等问题,设计了一种树枝粉碎装置,可通过喂料机构对树枝的强制性喂入,鼓式刀辊与定刀对树枝的连续切削,实现树枝的均匀连续粉碎。首先,设计了各关键部件结构参数;其次,基于树枝粉碎过程的动力学分析,分析了影响功耗的因素;再次,采用响应曲面试验,研究了刀具楔角、刀具后角、树枝喂入角对树枝剪切应力的影响;最后,使用Design-expert优化功能并根据加工工艺要求,确定了最优参数组合,并进行验证试验。响应曲面试验结果显示:试验因素的显著性主次顺序为刀具楔角、树枝喂入角、刀具后角;最优组合参数为刀具楔角为37.42°,树枝喂入角为45.41°,刀具后角为4.85°;结合实际加工条件以及工艺加工要求确定粉碎装置参数为刀具楔角40°,树枝喂入角45°,刀具后角5°。试验验证表明:最优组合下树枝粉碎合格率(木屑尺寸小于20mm占比)为96.41%,且小于5mm的占比为82.74%;对比于传统粉碎装置的作业效果,树枝粉碎合格率提升了7.91%,尺寸小于5mm的木屑占比提升了10.94%,优化效果明显。基于响应曲面设计的树枝粉碎装置具有作业质量高、粉碎效果均匀、功耗小的特点,可为树枝粉碎机的设计提供参考。

关键词：粉碎装置动力学分析响应曲面试验树枝

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棉花形态性状质量遗传分析与基因定位研究进展

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棉花学报 2018年第6期30卷 473-485页

作者：臧新山耿延会裴文锋吴嫚李兴丽张金发于霁雯棉花生物学国家重点实验室/中国农业科学院棉花研究所/农业农村部棉花生物学与遗传育种重点实验室河南安阳455000 New Mexico State University Las CrucesNew Mexico 88003USA

棉花质量性状的遗传分析和基因定位,对棉花育种工作者设计和培育新品种,提高育种效率,创新种质资源都有重要指导作用。棉花质量性状的研究始于20世纪初期,但都是基于形态上的观察。近年来,棉花基因组学研究的不断深入和分子标记遗传图... 详细信息

棉花质量性状的遗传分析和基因定位,对棉花育种工作者设计和培育新品种,提高育种效率,创新种质资源都有重要指导作用。棉花质量性状的研究始于20世纪初期,但都是基于形态上的观察。近年来,棉花基因组学研究的不断深入和分子标记遗传图谱的不断完善,为定位克隆棉花重要质量性状基因提供了便利。迄今为止,研究人员已对大部分质量性状基因进行了遗传连锁分析或染色体定位,其中部分质量性状的候选基因也已被鉴定出来。本文主要从质量性状遗传分析、分子标记定位和候选基因克隆几个方面系统地综述了植株颜色、叶片颜色、叶型、苞叶、花、蜜腺、腺体和纤维8类质量性状,为进一步研究棉花质量性状形成的分子机理和调控机制、定向转移基因及基因聚合育种等提供参考。

关键词：棉花质量性状染色体定位分子标记基因克隆

Atomically dispersed catalysts for small molecule electrooxidation in direct liquid fuel cells

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Journal of Energy Chemistry 2022年第5期31卷 439-453页

作者： jinfa Chang Guanzhi Wang Wei zhang Yang Yang NanoScience Technology Center University of Central FloridaOrlandoFL 32826USA Department of Materials Science and Engineering University of Central FloridaOrlandoFL 32826USA Department of Chemistry Renewable Energy and Chemical Transformation ClusterUniversity of Central FloridaOrlandoFL 32826USA

Direct liquid fuel cells(DLFCs) have received increasing attention because of their high energy densities,instant recharging abilities, simple cell structure, and facile storage and transport. The main challenge for the commercialization of DLFCs is the high loading requirement of platinum group metals(PGMs) as catalysts. Atomically dispersed catalysts(ADCs) have been brought into recent focus for DLFCs due to their well-defined active sites, high selectivity, maximal atom-utilization, and anti-poisoning property. In this review, we summarized the structure–property relationship for unveiling the underlying mechanisms of ADCs for DLFCs. More specifically, different types of fuels used in DLFCs such as methanol, formic acid,and ethanol were discussed. At last, we highlighted current challenges, research directions, and future outlooks towards the practical application of DLFCs.

关键词： Atomic dispersion Electrocatalyst Small molecule electrooxidation Direct liquid fuel cells

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无蜜腺对棉花生长发育影响的研究

华中农学院学报 1985年第4期 15-18页

作者：张金发孙济中刘金兰华中农学院农学系

采用经测验为近等基因系的两个BC3群体研究无蜜腺对棉花生长发育的影响,结果表明,有蜜腺和无蜜腺近等基因系的生长发育进展基本上是相似的。

关键词：蜜腺果枝数等基因系陆地棉高原棉成铃数生长动态伏前桃生长发育果节

表面电磁振荡激元波在光学薄膜研究中的应用(Ⅰ)

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光学学报 1985年第2期 151-156页

作者：唐晋发张殷刘兰芬浙江大学光学仪器系浙江大学光学仪器系

表面电磁振荡激元波（SPW）谐振是金属膜参数及其表面状态的十分灵敏的函数。因而利用SPW技术可以精确地确定金属膜及其表面污染层的光学常数。本文利用经典的薄膜光学方法讨论了SPW的激发及其理论计算。并在Kretschmann装置上测量了SP... 详细信息

表面电磁振荡激元波（SPW）谐振是金属膜参数及其表面状态的十分灵敏的函数。因而利用SPW技术可以精确地确定金属膜及其表面污染层的光学常数。本文利用经典的薄膜光学方法讨论了SPW的激发及其理论计算。并在Kretschmann装置上测量了SPW谐振反射率,借助于最优化技术计算了薄膜和表面层的光学常数。最后给出了Ag、Au、Cu和Al膜及以诸如Ag2S、CuOx和Al2O3等表面层的实验结果。

关键词：光学薄膜表面层金属膜金属薄膜表面污染最优化技术受抑全反射表面状态全反射角反射光

Digestive perianastomotic ulcerations after intestinal resection in children

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World Journal of Pediatric Surgery 2023年第3期6卷 123-128页

作者： Weicheng zhang jinfa Tou Department of Neonatal Surgery Zhejiang University School of Medicine Children's HospitalHangzhouZhejiangChina

Digestive perianastomotic ulceration(DPAU)is a rare complication after intestinal resection and anastomosis occurring at or near the anastomosis *** purpose of this review is to summarize the characteristics of DPAU,including the etiology,diagnosis and differential diagnosis,clinical manifestations,treatment,and future *** recent literature on DPAU was searched in PubMed,Embase,and Cochrane and then *** clinical manifestations of DPAU are mainly gastrointestinal symptoms such as bloody stool and chronic *** diagnosis of DPAU is *** diseases,such as Crohn’s disease,must be ruled out before a diagnosis can be *** addition,there are no clear treatment guidelines due to the high degree of heterogeneity in response to drugs and *** is recommended to adjust medication in time and combine various treatment *** addition,the mechanism that causes DPAU is not well understood;however,several possible mechanisms have been proposed,such as scar tissue ischemia and underlying ***,there is a high risk of relapses,and a long-term follow-up is *** issues remain to be solved in this area;therefore,more randomized controlled trials and studies should be carried out to further understand this disease.

关键词： diagnosis drugs treatment

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梵净山国家级自然保护区蝴蝶物种多样性调查

山地农业生物学报 2022年第6期41卷 6-13页

作者：田宇张金发田太安邢济春张兰蒙仕涛贵州梵净山国家级自然保护区管理局贵州江口554400 贵州大学昆虫研究所贵州贵阳550025

为弄清贵州梵净山国家级自然保护区的蝴蝶物种多样性,选择8种样地,于2019年9月至2021年11月期间进行蝴蝶物种调查,共获得蝴蝶2684只,隶属于5科112属212种(包含18个贵州新记录种),其中凤蝶科Papilionidae 5属17种258只,粉蝶科Pieridae 8... 详细信息

为弄清贵州梵净山国家级自然保护区的蝴蝶物种多样性,选择8种样地,于2019年9月至2021年11月期间进行蝴蝶物种调查,共获得蝴蝶2684只,隶属于5科112属212种(包含18个贵州新记录种),其中凤蝶科Papilionidae 5属17种258只,粉蝶科Pieridae 8属14种1032只,蛱蝶科Nymphalidae 49属108种876只,灰蝶科Lycaenidae 25属36种354只,弄蝶科Hesperiidae 25属37种164只。各科蝴蝶的种多样性指数以蛱蝶科最高为3.904,粉蝶科最低为1.456;属多样性指数以蛱蝶科最高为3.119,凤蝶科最低为0.548;蛱蝶科均匀度指数最高为0.834。8种样地中,Ⅵ样地的多样性指数(3.654)和丰富度指数(11.936)最高,Ⅶ样地的优势度指数(0.476)最高,Ⅳ样地的均匀度指数(0.893)最高。不同样地的群落相似性分析表明,Ⅲ样地与Ⅴ样地相似性系数最高为0.2860;Ⅵ样地与Ⅷ样地的相似性系数最低为0.0243。

关键词：贵州梵净山蝴蝶多样性调查新记录

Strong preciousmetal–metal oxide interaction for oxygen reduction reaction:A strategy for efficient catalyst design

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SusMat 2023年第1期3卷 2-20页

作者： Wei zhang jinfa Chang Yang Yang NanoScience Technology Center University of Central FloridaOrlandoFloridaUSA Department of Materials Science and Engineering University of Central FloridaOrlandoFloridaUSA Renewable Energy and Chemical Transformation Cluster University of Central FloridaOrlandoFloridaUSA Department of Chemistry University of Central FloridaOrlandoFloridaUSA The StephenW.Hawking Center for Microgravity Research and Education University of Central FloridaOrlandoFloridaUSA

Oxygen reduction reaction(ORR)is an electrochemical reaction in which dissolved oxygen in an electrolyte is reduced toOH−/H2Owhen receiving *** reaction plays a crucial role in shaping the efficiency of both metal-air batteries and fuel cells,and precious metals are the dominant catalysts carrying out the ORR in their ***,how to manipulate the electronic structure of precious metals as active sites to further promote ORR performance and maximize the utilization rate is still under *** oxide serves as suitable and promising support that can strongly interact with precious metals for both activity and durability ***,we present recent research updates on strong precious metal-metal oxide interaction(SPMMOI)utilized in *** start by introducing the background of ORR,the issues to be solved,and its practical applications followed by a thorough discussion of the reaction mechanism and comprehensive evaluation protocols of *** then provide a complete understanding of theworking principle of SPMMOI and highlight the related ***,we summarize the merits of the precious metal-metal oxide systemand propose the research direction aswell as some urgent problems to be addressed in the future.

关键词： electrocatalysis electronic structure oxide support oxygen reduction reaction strong precious metal-metal oxide interaction

Low carbon alcohol fuel electrolysis of hydrogen generation catalyzed by a novel and effective Pt–CoTe/C bifunctional catalyst system

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Green Energy & Environment 2024年第4期9卷 758-770页

作者： Yang Zhou Lice Yu jinfa Chang Ligang Feng Jiujun zhang School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou225002JiangsuChina NanoScience Technology Center University of Central FloridaOrlandoFL32826USA College of Sciences&Institute for Sustainable Energy Shanghai UniversityShanghai200444China

Low carbon alcohol fuels electrolysis under ambient conditions is promising for green hydrogen generation instead of the traditional alcohol fuels steam reforming technique,and highly efficient bifunctional catalysts for membrane electrode fabrication are required to drive the electrolysis ***,the efficient catalytic promotion effect of a novel catalyst promoter,CoTe,on Pt is demonstrated for low carbon alcohol fuels of methanol and ethanol electrolysis for hydrogen *** and density functional theory calculation results indicate that the optimized electronic structure of Pt–CoTe/C resulting from the synergetic effect between Pt and CoTe further regulates the adsorption energies of CO and H*that enhances the catalytic ability for methanol and ethanol ***,the good water activation ability of CoTe and the strong electronic effect of Pt and CoTe increased the tolerance ability to the poisoning species as demonstrated by the CO-stripping *** high catalytic kinetics and stability,as well as the promotion effect,were also carefully ***,71.9%and 75.5%of the initial peak current density was maintained after 1000 CV cycles in acid electrolyte for methanol and ethanol oxidation;and a low overpotential of 30 and 35 mV was required to drive the hydrogen evolution reaction in methanol and ethanol solution at the current density of 10 mA cm^(-2).In the two-electrode system for alcohol fuels electrolysis,using the optimal Pt–CoTe/C catalyst as bi-functional catalysts,the cell potential of 0.66 V(0.67 V)was required to achieve 10 mA cm^(-2) for methanol(ethanol)electrolysis,much smaller than that of water electrolysis(1.76 V).The current study offers a novel platform for hydrogen generation via low carbon alcohol fuel electrolysis,and the result is helpful to the catalysis mechanism understanding of Pt assisted by the novel promoter.

关键词： Methanol electrolysis Ethanol electrolysis Cobalt telluride Pt-based electrocatalyst Hydrogen evolution reaction