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植物源生物炭材料的制备及其在农药残留领域中的应用进展

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色谱 2022年第6期40卷 499-508页

作者：张贤钊甄大卫刘丰茂彭庆蓉王宗义中国农业大学理学院应用化学系农药创新中心北京100193 北京农学院农产品有害微生物及农残安全检测与控制北京市重点实验室北京102206

随着农药的广泛使用,其已普遍存在于环境中,对人们的身体健康产生巨大影响。因此,环境中农药残留的去除和分析检测对保护人体安全健康至关重要。同时,农药在环境中残留浓度低,需要一种对目标物有较强选择性和富集作用,并对环境影响小的... 详细信息

随着农药的广泛使用,其已普遍存在于环境中,对人们的身体健康产生巨大影响。因此,环境中农药残留的去除和分析检测对保护人体安全健康至关重要。同时,农药在环境中残留浓度低,需要一种对目标物有较强选择性和富集作用,并对环境影响小的前处理吸附剂。植物源生物炭是由植物源生物质作为碳源衍生得到的材料,其比表面积大、孔容量高、表面官能团可调节,且环境相容性好,其原料植物源生物质的价格低廉、来源广泛并可再生,是一种廉价高效的吸附剂。该文主要综述了近10年来植物源生物炭用于环境中农药残留去除和分析检测前处理的应用进展。其中在农药残留去除方面的应用主要包括降低农药在土壤中的移动性,修复手性农药造成的污染,负载降解农药的细菌及作为化肥的缓释载体。在农药残留分析检测前处理方面,植物源生物炭可用作分散固相萃取、固相微萃取和磁性固相萃取的吸附剂来选择性吸附水果和蔬菜中的有机磷类和三唑类农药,以及水环境中的有机氯类农药。另外,还介绍了植物源生物炭的吸附机理,详细阐述了基于计算模拟如密度泛函理论、分子动力学模拟和巨正则蒙特卡洛模拟的吸附机理研究并讨论了其优势。最后,总结了植物源生物炭在农药去除和农药残留分析检测前处理方面应用的优势,指出了其在农药残留领域应用待解决的问题。

关键词：制备方法农药去除残留分析理论计算植物源生物炭材料综述

工件加工可拒绝的无界批量分批排序问题的几点探讨(英文)

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运筹学学报 2009年第3期13卷 23-30页

作者：张咸昭蔡增霞任剑锋临沂师范学院数学系临沂276005 曲阜师范大学运筹与管理学院日照276826

本文对两个加工可拒绝的无界批量分批排序问题1|B≥n,rej|∑w_jT_j+TP和1|B≥n,rej|∑w_jU_j+TP进行了研究,对这两个问题分别给出了伪多项式时间算法和(FPTAS)近似算法.目前为止它们都是比较好的精确算法和近似算法.

关键词：运筹学可拒绝 NP-困难伪多项式时间 FPTAS

大黄颗粒保留灌肠辅助治疗重症急性胰腺炎的疗效与护理

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全科护理 2014年第26期12卷 2417-2419页

作者：孙春田任广琴张宪昭广东省中山市中医院

[目的]探讨大黄颗粒保留灌肠辅助治疗重症急性胰腺炎(SAP)的临床疗效与相应的护理措施。[方法]将40例SAP病人随机分为观察组和对照组各20例,两组均按照SAP的常规处理原则进行治疗,观察组配合应用大黄颗粒保留灌肠,并给予相应的护理措施... 详细信息

[目的]探讨大黄颗粒保留灌肠辅助治疗重症急性胰腺炎(SAP)的临床疗效与相应的护理措施。[方法]将40例SAP病人随机分为观察组和对照组各20例,两组均按照SAP的常规处理原则进行治疗,观察组配合应用大黄颗粒保留灌肠,并给予相应的护理措施,观察两组病人腹痛缓解时间、腹胀缓解时间、腹部压痛消失时间、自主通便时间、C反应蛋白(CRP)恢复正常时间、住院时间、中转手术的比例。[结果]观察组病人腹痛缓解时间、腹胀缓解时间、腹部压痛消失时间、自主通便时间、CRP恢复正常时间、住院时间均短于对照组(P<0.05)。[结论]大黄颗粒保留灌肠辅助治疗SAP有较好的疗效。

关键词：重症急性胰腺炎大黄颗粒保留灌肠辅助治疗护理

Preparation of silver nanoparticles through the reduction of straw-extracted lignin and its antibacterial hydrogel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 504-514页

作者： Lou zhang Shuo Li Fu Tang Jingkai zhang Yuetong Kang Hean zhang Lidong Li State Key Laboratory for Advanced Metals and Materials School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial ***,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water *** this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing *** analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag *** surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their *** the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite *** inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag *** prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings.

关键词： silver nanoparticles hydrogel straw extraction antibacterial

当归内酯和2-甲基呋喃合成可再生生物柴油前驱体

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生物质化学工程 2017年第5期51卷 1-6页

作者：王伟季晓晖葛红光李志洲邵先钊张强陕西理工大学化学与环境科学学院陕西汉中723001 陕西省催化基础与应用重点实验室陕西汉中723001

以生物质衍生的当归内酯与2-甲基呋喃为原料,杂多酸为催化剂,经羟烷基化或烷基化反应生成4,4-二(5-甲基呋喃-2-基)戊酸,然后加氢制得可再生生物柴油前驱体4,4-二(5-甲基四氢呋喃-2-基)-1-戊醇和双(5-甲基四氢呋喃-2-基)乙烷。首先,考察... 详细信息

以生物质衍生的当归内酯与2-甲基呋喃为原料,杂多酸为催化剂,经羟烷基化或烷基化反应生成4,4-二(5-甲基呋喃-2-基)戊酸,然后加氢制得可再生生物柴油前驱体4,4-二(5-甲基四氢呋喃-2-基)-1-戊醇和双(5-甲基四氢呋喃-2-基)乙烷。首先,考察了硅钨酸、磷钼酸和硅钼酸催化剂对羟烷基化/烷基化反应的影响,并对催化剂用量、反应温度和时间进行了优化,结果表明,硅钨酸的催化性最高,在反应温度为60℃、硅钨酸的用量为0.05 g、反应时间为60 min条件下4,4-二(5-甲基呋喃-2-基)戊酸产率达到70.5%。然后,考察了Pd/C、Ru/C和Pt/C催化剂对当归内酯与2-甲基呋喃羟烷基化/烷基化产物的加氢反应,Ru/C催化剂表现出最好的活性和选择性,4,4-二(5-甲基四氢呋喃-2-基)-1-戊醇和双(5-甲基四氢呋喃-2-基)乙烷产率分别为60.5%和24.6%。最后对Ru/C催化剂的稳定性进行了考察,在24 h的反应时间内催化剂表现出良好的稳定性,活性没有明显下降。获得的4,4-二(5-甲基四氢呋喃-2-基)-1-戊醇和双(5-甲基四氢呋喃-2-基)乙烷混合物可作为柴油前驱体。

关键词：羟烷基化/烷基化加氢生物柴油前驱体当归内酯 2-甲基呋喃

Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： Feng zhang Chenyang zhang Linlin Wu Wei Sun Hongliang zhang Jianhua Chen Yong Pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

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臭氧去除果蔬中农药残留研究进展

农药学学报 2023年第1期25卷 35-50页

作者：李晓晗吴舸张贤钊刘成成彭庆蓉赵占平刘丰茂中国农业大学应用化学系农药创新研究中心北京100193 无限极(中国)有限公司广州510663

水果、蔬菜中农药残留的清洗去除研究是进一步提升食品安全的保证。臭氧处理技术是去除农药残留的常用方法之一。本文主要介绍了用于去除水果蔬菜上农药残留的臭氧处理技术,包括:臭氧产生方式、应用形式以及臭氧与其他方法联合处理技术... 详细信息

水果、蔬菜中农药残留的清洗去除研究是进一步提升食品安全的保证。臭氧处理技术是去除农药残留的常用方法之一。本文主要介绍了用于去除水果蔬菜上农药残留的臭氧处理技术,包括:臭氧产生方式、应用形式以及臭氧与其他方法联合处理技术的应用,综述了影响农药残留去除效果的因素,也介绍了臭氧去除农药残留的同时对果蔬外观、营养等影响,进一步探究了臭氧去除农药残留的作用机制和应用价值,旨在为臭氧清洗技术用于去除果蔬农药残留的研究提供理论和应用参考。

关键词：食品安全果蔬农药残留臭氧清洗作用机制

Glucocorticoid receptor signaling in the brain and its involvement in cognitive function

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Neural Regeneration Research 2025年第9期20卷 2520-2537页

作者： Chonglin Su Taiqi Huang Meiyu zhang Yanyu zhang Yan Zeng Xingxing Chen Brain Science and Advanced Technology Institute Hubei Province Key Laboratory of Occupational Hazard Identification and ControlSchool of MedicineWuhan University of Science and TechnologyWuhanHubei ProvinceChina

The hypothalamic-pituitary-adrenal axis regulates the secretion of glucoco rticoids in response to environmental *** the brain,a nuclear receptor transcription fa ctor,the glucocorticoid recepto r,is an important component of the hypothalamicpituitary-a d renal axis's negative feedback loop and plays a key role in regulating cognitive equilibrium and *** glucoco rticoid receptor influences cognitive processes,including glutamate neurotransmission,calcium signaling,and the activation of brain-derived neurotrophic factor-mediated pathways,through a combination of genomic and non-genomic *** interactions within the central nervous system can alter the expression and activity of the glucocorticoid receptor,there by affecting the hypothalamic-pituitary-a d renal axis and stress-related cognitive *** appropriate level of glucocorticoid receptor expression can improve cognitive function,while excessive glucocorticoid receptors or long-term exposure to glucoco rticoids may lead to cognitive *** with cognitive impairment-associated diseases,such as Alzheimer's disease,aging,depression,Parkinson's disease,Huntington's disease,stroke,and addiction,often present with dysregulation of the hypothalamic-pituitary-adrenal axis and glucocorticoid receptor *** review provides a comprehensive overview of the functions of the glucoco rticoid receptor in the hypothalamic-pituitary-a d renal axis and cognitive *** emphasizes that appropriate glucocorticoid receptor signaling fa cilitates learning and memory,while its dysregulation can lead to cognitive *** provides clues about how glucocorticoid receptor signaling can be targeted to ove rcome cognitive disability-related disorders.

关键词： brain-derived neurotrophic factor calcium signaling glucocorticoid receptor glucocorticoid glutamate transmission hypothalamic-pituitary-adrenal axis long-term potentiation neurocognitive disorders neuroplasticity stress

小鼠内淋巴囊原代上皮细胞L型钙离子通道定位表达

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山东大学学报（医学版） 2021年第10期59卷 17-22,56页

作者：隋荣翠韩书慧张宪昭范新泰王娜侯凌霄许安廷山东大学第二医院耳鼻咽喉头颈外科山东济南250033 济宁市第一人民医院耳鼻咽喉头颈外科山东济宁272100

目的探讨C57BL/6小鼠内淋巴囊原代上皮细胞中电压门控钙离子通道定位表达。方法选取2日龄C57BL/6(P2B6)小鼠60只,P2B6小鼠8只麻醉处死取得颞骨标本,体视显微镜下定位内淋巴囊位置,提取内淋巴囊原代细胞并在低血清状态下培养。P2B6小鼠5... 详细信息

目的探讨C57BL/6小鼠内淋巴囊原代上皮细胞中电压门控钙离子通道定位表达。方法选取2日龄C57BL/6(P2B6)小鼠60只,P2B6小鼠8只麻醉处死取得颞骨标本,体视显微镜下定位内淋巴囊位置,提取内淋巴囊原代细胞并在低血清状态下培养。P2B6小鼠52只处理同上,颞骨标本用4%甲醛固定后脱钙包埋,采用免疫组织荧光技术和免疫细胞荧光技术定性原代内淋巴囊上皮细胞并确定L型钙离子通道表达。结果内淋巴囊上皮细胞在P2B6小鼠内淋巴囊中排列紧密,可见细胞聚集呈嵴状突起,胞体较小,细胞呈椭圆状,以扁平上皮为主,细胞培养光镜观察为不规则铺路石样,细胞形态大小不一,胞浆丰富,核椭圆形且大。免疫荧光检测显示L型Ca^(2+)通道在内淋巴囊上皮细胞膜上均呈均匀表达,细胞核上高表达。结论小鼠原代内淋巴囊上皮细胞中L-型电压依赖钙离子通道α1C亚基(CACNA1C)、L-型电压依赖钙离子通道α1S亚基(CACNA1S)、L-型电压依赖钙离子通道α1D亚基(Cav1.3/CACNA1D)表达为阳性,为细胞功能学实验提供依据,有利于进一步研究内淋巴囊维持稳态的机制。

关键词：内淋巴囊原代上皮细胞 L型Ca^(2+)通道免疫荧光小鼠