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基于EVA法的永辉超市企业价值评估
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作者 岑燕 吴自彬 《价值工程》 2026年第3期68-70,共3页
生鲜零售行业围绕生鲜产品销售展开,市场规模不断扩大且前景良好。文章通过选取生鲜零售行业的永辉超市为案例,运用EVA评估模型,详细分析行业概况后,构建永辉超市EVA价值评估模型,计算出2021-2023年相关指标,揭示其经营状况变化,预测未... 生鲜零售行业围绕生鲜产品销售展开,市场规模不断扩大且前景良好。文章通过选取生鲜零售行业的永辉超市为案例,运用EVA评估模型,详细分析行业概况后,构建永辉超市EVA价值评估模型,计算出2021-2023年相关指标,揭示其经营状况变化,预测未来EVA现值以评估企业价值。研究结果有助于深入理解永辉超市的价值创造能力,为利益相关者提供参考,同时也为深入探究EVA评估模型在零售企业的应用特点及局限性提供实证,推动企业价值评估理论与实践在零售领域的发展。 展开更多
关键词 企业价值评估 eva模型 永辉超市
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Chitosan alleviates symptoms of Parkinson's disease by reducing acetate levels, which decreases inflammation and promotes repair of the intestinal barrier and blood–brain barrier
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作者 Yinying Wang Rongsha Chen +7 位作者 Guolin Shi Xinwei Huang Ke Li Ruohua Wang Xia Cao Zhongshan Yang Ninghui Zhao Jinyuan Yan 《Neural Regeneration Research》 2026年第1期377-391,共15页
Studies have shown that chitosan protects against neurodegenerative diseases. However, the precise mechanism remains poorly understood. In this study, we administered chitosan intragastrically to an MPTP-induced mouse... Studies have shown that chitosan protects against neurodegenerative diseases. However, the precise mechanism remains poorly understood. In this study, we administered chitosan intragastrically to an MPTP-induced mouse model of Parkinson's disease and found that it effectively reduced dopamine neuron injury, neurotransmitter dopamine release, and motor symptoms. These neuroprotective effects of chitosan were related to bacterial metabolites, specifically shortchain fatty acids, and chitosan administration altered intestinal microbial diversity and decreased short-chain fatty acid production in the gut. Furthermore, chitosan effectively reduced damage to the intestinal barrier and the blood–brain barrier. Finally, we demonstrated that chitosan improved intestinal barrier function and alleviated inflammation in both the peripheral nervous system and the central nervous system by reducing acetate levels. Based on these findings, we suggest a molecular mechanism by which chitosan decreases inflammation through reducing acetate levels and repairing the intestinal and blood–brain barriers, thereby alleviating symptoms of Parkinson's disease. 展开更多
关键词 acetate adenosine 5′-monophosphate-activated protein kinase blood–brain barrier CHITOSAN dopamine neurons INFLAMMATION intestinal barrier Parkinson's disease peroxisome proliferator-activated receptor delta short-chain fatty acids
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EVA胶粉对超高性能工程水泥基复合材料性能的影响
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作者 黄杰 水中和 +3 位作者 亓习博 刘家宝 黄周龙 何静 《硅酸盐通报》 北大核心 2025年第8期2752-2761,共10页
分别采用低醋酸乙烯(VA)含量的刚性乙烯-醋酸乙烯共聚物(EVA)胶粉、高VA含量的柔性EVA胶粉和以月桂酸乙烯酯为基础的疏水性EVA胶粉对超高性能工程水泥基复合材料(UHPECC)进行改性,分析三种不同类型EVA对UHPECC流动度、抗压强度、抗折强... 分别采用低醋酸乙烯(VA)含量的刚性乙烯-醋酸乙烯共聚物(EVA)胶粉、高VA含量的柔性EVA胶粉和以月桂酸乙烯酯为基础的疏水性EVA胶粉对超高性能工程水泥基复合材料(UHPECC)进行改性,分析三种不同类型EVA对UHPECC流动度、抗压强度、抗折强度、抗拉强度、极限拉伸应变、粘结强度、界面抗渗性能、收缩特性、水化程度、孔结构特性和微观特征的影响。结果表明:单掺三种类型EVA后,UHPECC的流动度和抗压强度会降低,但抗折强度、抗拉强度、粘结强度和界面抗渗性能会提升;刚性EVA组在抗折强度、抗拉强度、粘结强度方面表现最好,柔性EVA组在流动度、极限拉伸应变和降低收缩方面表现最好,疏水性EVA在界面抗渗性能方面表现最好;EVA的掺入会降低UHPECC的水化程度,同时降低孔隙率,增强纤维与基体之间的附着力,也会增加UHPECC与普通混凝土界面缺陷处的密实度,进而改善UHPECC的性能。 展开更多
关键词 eva胶粉 超高性能工程水泥基复合材料 强度 极限拉伸应变 粘结强度 界面抗渗性能
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液体硅树脂的陶瓷化行为及对EVA/MH的协效阻燃作用
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作者 张婧 刘思阳 +4 位作者 陈屿恒 王静霞 倪茂君 彭朝荣 张恺凯 《有机硅材料》 2025年第2期7-16,共10页
利用二甲基二乙氧基硅烷和乙烯基三乙氧基硅烷在酸催化作用下共水解缩合,制备了系列具有类笼形网络结构的液体硅树脂,并考察了它们在1000℃高温下的陶瓷化形为。进一步研究了陶瓷化转化率较高的DT11液体硅树脂在乙烯醋酸乙烯共聚物(EVA)... 利用二甲基二乙氧基硅烷和乙烯基三乙氧基硅烷在酸催化作用下共水解缩合,制备了系列具有类笼形网络结构的液体硅树脂,并考察了它们在1000℃高温下的陶瓷化形为。进一步研究了陶瓷化转化率较高的DT11液体硅树脂在乙烯醋酸乙烯共聚物(EVA)/氢氧化镁(MH)共混体系中的协效作用,及其对复合材料阻燃性和燃烧行为的影响。结果表明,DT11与MH的协同阻燃效果明显,能够提高复合材料的热稳定性,减少可燃性气体的生成,改善成炭性。当EVA、MH、DT11的质量比为50∶48∶2时,极限氧指数达到47%,较EVA/MH的增幅为88%。EVA/MH/DT11复合材料在燃烧过程中快速形成结构化炭层,有效阻隔了热量和可燃性气体的传递,使热释放速率下降35.1%,总热释放量减少13.5%,总烟释放量增加15.3%。 展开更多
关键词 液体硅树脂 陶瓷化 阻燃 氢氧化镁 eva
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光伏级EVA关键物性指标测试方法研究
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作者 方义 赵勇森 +1 位作者 胡斌 刘巍 《分析仪器》 2025年第4期79-83,共5页
以光伏级EVA(乙烯-醋酸乙烯共聚物)为原料,对比分析了不同测试条件下的VA(醋酸乙烯)含量、熔体质量流动速率(MFR)、熔融峰温及薄膜晶点数量,结果表明,红外光谱法测得的VA含量较热重法高约1%,125℃/2.16kg间接法测试的MFR较190℃/2.16kg... 以光伏级EVA(乙烯-醋酸乙烯共聚物)为原料,对比分析了不同测试条件下的VA(醋酸乙烯)含量、熔体质量流动速率(MFR)、熔融峰温及薄膜晶点数量,结果表明,红外光谱法测得的VA含量较热重法高约1%,125℃/2.16kg间接法测试的MFR较190℃/2.16kg直接法高约1.2g/10min,20℃/min升温速率测试的熔融峰温较10℃/min升温速率的结果高约1.1℃,加工温度150℃下流延法制得的薄膜晶点数量较125℃下大幅降低。测试条件的不同是EVA上下游企业反馈产品质量指标差异的主要原因,热重法测试VA含量简单易操作,间接法测试MFR更科学合理,建议国内尽快建立光伏级EVA的团体或行业标准。 展开更多
关键词 光伏级 eva 测试方法 VA含量 升温速率 晶点数量
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EVA与实物期权估值法视角下芯片企业价值评估方法研究——以中芯国际为例 被引量:1
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作者 王明国 邵梦娜 《现代营销(上)》 2025年第7期115-117,共3页
在竞争激烈且复杂多变的商业环境中,准确地评估企业价值对于企业战略决策、投融资规划以及市场定位等方面至关重要。目前,很多企业敏锐地察觉到科学、精准评估企业价值的重要性,从而纷纷运用EVA-BS模型开展企业价值评估工作。本文通过... 在竞争激烈且复杂多变的商业环境中,准确地评估企业价值对于企业战略决策、投融资规划以及市场定位等方面至关重要。目前,很多企业敏锐地察觉到科学、精准评估企业价值的重要性,从而纷纷运用EVA-BS模型开展企业价值评估工作。本文通过组合模型对芯片企业价值进行评估,发现组合模型不仅能为投资者提供决策依据,也有助于企业管理层明确自身价值定位。 展开更多
关键词 eva模型 实物期权估值法 企业价值评估
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ZBTB18通过转录调控EVA1B激活PI3K/AKT通路促进胶质瘤恶性进展
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作者 王华富 陈旭东 +1 位作者 周小鹏 陈陶陶 《温州医科大学学报》 2025年第9期731-738,共8页
目的:鉴定新型促癌因子EVA1B的临床意义,解析其调控胶质瘤恶性表型的作用机制,并探索上游转录调控网络。方法:通过RT-qPCR、Western blot和免疫组化检测临床样本中EVA1B表达;利用CCK-8、克隆形成、划痕及Transwell实验分析EVA1B对胶质... 目的:鉴定新型促癌因子EVA1B的临床意义,解析其调控胶质瘤恶性表型的作用机制,并探索上游转录调控网络。方法:通过RT-qPCR、Western blot和免疫组化检测临床样本中EVA1B表达;利用CCK-8、克隆形成、划痕及Transwell实验分析EVA1B对胶质瘤细胞(LN229/U138)增殖、迁移的影响;采用RNA-seq、Western blot验证下游通路;通过双荧光素酶报告基因和过表达/敲除实验研究ZBTB18的转录调控作用。结果:EVA1B在胶质瘤组织表达显著高于癌旁组织(P<0.05),且随WHO分级升高而递增(III+IV级>I+II级,P<0.05)。Kaplan-Meier分析显示:与EVA1B低表达患者相比,高表达EVA1B患者生存期显著缩短(P<0.05)。在胶质瘤细胞系中过表达EVA1B显著促进细胞增殖和迁移能力,敲低EVA1B则抑制肿瘤细胞增殖和迁移能力(均P<0.05)。RNA-seq联合Western blot证实EVA1B通过上调PI3K/AKT通路介导增殖和迁移表型。进一步发现,ZBTB18可能直接结合EVA1B启动子,抑制其转录活性(P<0.05)。在胶质瘤细胞中过表达ZBTB18可抑制胶质瘤细胞增殖和迁移表型。结论:在胶质瘤细胞中EVA1B作为ZBTB18下游靶基因,通过激活PI3K/AKT通路驱动胶质瘤细胞增殖和迁移表型,其高表达提示不良预后,为潜在治疗靶点。 展开更多
关键词 ZBTB18 eva1B 脑胶质瘤 转录调控
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Anti-inflammatory properties of the short-chain fatty acids acetate and propionate:A study with relevance to inflammatory bowel disease 被引量:92
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作者 Sofia Tedelind Fredrik Westberg +1 位作者 Martin Kjerrulf Alexander Vidal 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第20期2826-2832,共7页
AIM: To compare the anti-inflammatory properties of butyrate with two other SCFAs, namely acetate and propionate, which have less well-documented effects on inflammation. METHODS: The effect of SCFAs on cytokine rel... AIM: To compare the anti-inflammatory properties of butyrate with two other SCFAs, namely acetate and propionate, which have less well-documented effects on inflammation. METHODS: The effect of SCFAs on cytokine release from human neutrophils was studied with EHSA. SCFA- dependent modulation of NF-κB reporter activity was assessed in the human colon adenocarcinoma cell line, Colo320DM. Finally, the effect of SCFAs on gene expression and cytokine release, measured with RT-PCR and ELISA, respectively, was studied in mouse colon organ cultures established from colitic mice. RESULTS: Acetate, propionate and butyrate at 30 mmol/L decreased LPS-stimulated TNFα release from neutrophils, without affecting IL-8 protein release. All SCFAs dose dependently inhibited NF-κB reporter activity in Colo320DM cells. Propionate dose-dependently suppressed IL-6 mRNA and protein release from colon organ cultures and comparative studies revealed that propionate and butyrate at 30 mmol/L caused a strong inhibition of immune-related gene expression, whereas acetate was less effective. A similar inhibition was achieved with the proteasome inhibitor MG-132, but not the p38 MAPK inhibitor SB203580. All SCFAs decreased IL-6 protein release from organ cultures. CONCLUSION: In the present study propionate and butyrate were equipotent, whereas acetate was less effective, at suppressing NF-κB reporter activity, immune-related gene expression and cytokine release in vitro. Our findings suggest that propionate and acetate, in addition to butyrate, could be useful in the treatment of inflammatory disorders, including IBD. 展开更多
关键词 NEUTROPHILS Epithelial cells COLITIS Infla- mmation Short-chain fatty acids acetate PROPIONATE BUTYRATE NF-KB Cytokines
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基于EVA的报喜鸟新零售转型绩效研究
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作者 张国富 张燕华 《中小企业管理与科技》 2025年第11期128-130,共3页
新零售转型对我国零售企业的发展与市场竞争力产生较深影响,成为推动零售行业创新发展的核心动力。新零售转型中智能技术研发、全渠道建设的资本投入需关注长期价值创造而非短期利润,技术驱动下柔性供应链的效益需通过资本效率量化,单... 新零售转型对我国零售企业的发展与市场竞争力产生较深影响,成为推动零售行业创新发展的核心动力。新零售转型中智能技术研发、全渠道建设的资本投入需关注长期价值创造而非短期利润,技术驱动下柔性供应链的效益需通过资本效率量化,单一传统的财务指标难以全面揭示企业经营实绩与价值创造潜能。论文选择新零售转型领先企业报喜鸟为案例研究对象,以EVA为切入点,探究其新零售转型的成效,希望能为服装业其他企业提供有价值的参考。 展开更多
关键词 新零售 报喜鸟 绩效研究 eva
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不同偶联剂改性铜尾矿对PP/EVA复合材料性能影响
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作者 黄峰 夏忠浩 +6 位作者 万仁康 力文玉 蔡国俊 张继梅 华苏东 张亚男 延伟康 《包装工程》 北大核心 2025年第1期57-64,共8页
目的解决铜尾矿(CT)堆积对生态环境的严重影响,探索改性铜尾矿作为增强填料在PP/EVA共混物中的高效利用。方法使用硅烷偶联剂KH550、KH560和KH570对铜尾矿进行表面改性以改善其疏水性,评估不同偶联剂改性铜尾矿填充对复合材料力学性能... 目的解决铜尾矿(CT)堆积对生态环境的严重影响,探索改性铜尾矿作为增强填料在PP/EVA共混物中的高效利用。方法使用硅烷偶联剂KH550、KH560和KH570对铜尾矿进行表面改性以改善其疏水性,评估不同偶联剂改性铜尾矿填充对复合材料力学性能和热性能的影响,并通过SEM分析改性铜尾矿在复合材料中的分散情况及与基体的界面结合情况。结果KH570改性的铜尾矿复合材料拉伸强度达到17.23 MPa、弯曲强度达到28.06 MPa、缺口冲击强度达到15.31 kJ/m^(2),热稳定性显著提高,最大降解温度tmax为498℃,且SEM显示改性铜尾矿在复合材料中分散均匀,与树脂基体界面结合良好,应力集中现象减少。结论研究结果为废弃铜尾矿的高效利用提供了新思路,为其在树脂基复合材料中的应用奠定了基础,实现了对铜尾矿高效利用的研究目标。 展开更多
关键词 聚丙烯 乙烯-醋酸乙烯共聚物 铜尾矿 表面改性 力学性能
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EVA树脂产业现状及应用进展
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作者 刘哲 吕海洋 +3 位作者 嵇媛 杨鹏 董鑫 李连鹏 《弹性体》 2025年第5期87-92,共6页
介绍了乙烯-醋酸乙烯酯共聚物(EVA)树脂的生产技术和我国EVA企业新增产能情况,总结梳理了下游应用技术研究进展。针对国际新形势和国内的EVA市场竞争格局情况,从产品研发、产业布局等方面提出了产业展望和发展建议。
关键词 乙烯-醋酸乙烯酯共聚物 双碳目标 应用发展
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Evaluation of curcumin and copper acetate against Salmonella Typhimurium infection,intestinal permeability,and cecal microbiota composition in broiler chickens 被引量:4
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作者 Anaisa ALeyva-Diaz Daniel Hernandez-Patlan +8 位作者 Bruno Solis-Cruz Bishnu Adhikari Young Min Kwon Juan D.Latorre Xochitl Hernandez-Velasco Benjamin Fuente-Martinez Billy M.Hargis Raquel Lopez-Arellano Guillermo Tellez-Isaias 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第3期1019-1030,共12页
Background:Interest in the use of natural feed additives as an alternative to antimicrobials in the poultry industry has increased in recent years because of the risk of bacterial resistance.One of the most studied gr... Background:Interest in the use of natural feed additives as an alternative to antimicrobials in the poultry industry has increased in recent years because of the risk of bacterial resistance.One of the most studied groups are polyphenolic compounds,given their advantages over other types of additives and their easy potentiation of effects when complexes are formed with metal ions.Therefore,the objective of the present study was to evaluate the impact of dietary supplementation of copper acetate(CA),curcumin(CR),and their combination(CA-CR)against Salmonella Typhimurium colonization,intestinal permeability,and cecal microbiota composition in broiler chickens through a laboratory Salmonella infection model.S.Typhimurium recovery was determined on day 10 post-challenge by isolating Salmonella in homogenates of the right cecal tonsil(12 chickens per group)on Xylose Lysine Tergitol-4(XLT-4)with novobiocin and nalidixic acid.Intestinal integrity was indirectly determined by the fluorometric measurement of fluorescein isothiocyanate dextran(FITC-d)in serum samples from blood obtained on d 10 post-S.Typhimurium challenge.Finally,microbiota analysis was performed using the content of the left caecal tonsil of 5 chickens per group by sequencing V4 region of 16S rRNA gene.Results:The results showed that in two independent studies,all experimental treatments were able to significantly reduce the S.Typhimurium colonization in cecal tonsils(CT,P<0.0001)compared to the positive control(PC)group.However,only CA-CR was the most effective treatment in reducing S.Typhimurium counts in both independent studies.Furthermore,the serum fluorescein isothiocyanate dextran(FITC-d)concentration in chickens treated with CR was significantly lower when compared to PC(P=0.0084),which is related to a decrease in intestinal permeability and therefore intestinal integrity.The effect of dietary treatments in reducing Salmonella was further supported by the analysis of 16S rRNA gene sequences using Linear discriminant analysis effect size(LEfSe)since Salmonella was significantly enriched in PC group(LDA score>2.0 and P<0.05)compared to other groups.In addition,Coprobacillus,Eubacterium,and Clostridium were significantly higher in the PC group compared to other treatment groups.On the contrary,Fecalibacterium and Enterococcus in CR,unknown genus of Erysipelotrichaceae at CA-CR,and unknown genus of Lachnospiraceae at CA were significantly more abundant respectively.Conclusions:CR treatment was the most effective treatment to reduce S.Typhimurium intestinal colonization and maintain better intestinal homeostasis which might be achieved through modulation of cecal microbiota. 展开更多
关键词 Broiler chickens Copper acetate CURCUMIN Intestinal permeability Microbiota composition Salmonella Typhimurium
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Design and evaluation of an extended-release matrix tablet formulation; the combination of hypromellose acetate succinate and hydroxypropylcellulose 被引量:1
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作者 Sachiko Fukui Hideki Yano +2 位作者 Shuichi Yada Tsuyoshi Mikkaichi Hidemi Minami 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2017年第2期149-156,共8页
The purpose of this study was to develop an extended-release(ER) matrix tablet that shows robust dissolution properties able to account for the variability of pH and mechanical stress in the GI tract using a combinati... The purpose of this study was to develop an extended-release(ER) matrix tablet that shows robust dissolution properties able to account for the variability of pH and mechanical stress in the GI tract using a combination of enteric polymer and hydrophilic polymer. Hypromellose acetate succinate(HPMCAS) and hydroxypropylcellulose(HPC) were selected as ER polymers for the ER matrix tablet(HPMCAS/HPC ER matrix tablet). Oxycodone hydrochloride was employed as a model drug. Dissolution properties of the HPMCAS/HPC ER matrix tablets were evaluated and were not affected by the pH of the test medium or paddle rotating speed.In a USP apparatus 3(bio-relevant dissolution method), dissolution profiles of the HPMCAS/HPC ER matrix tablets containing oxycodone hydrochloride were similar to that of the reference product(OxyC ontin). Moreover, in vivo performance after oral administration of the HPMCAS/HPC ER matrix tablets to humans was simulated by GastroP lus based on dissolution profiles from the USP apparatus 3. The plasma concentration-time profile simulated was similar to that of the reference product. These results suggest that the combination of HPMCAS and HPC shows a robust dissolution profile against pH and paddle rotating speed and indicates the appropriate extended-release profile in humans. 展开更多
关键词 EXTENDED-RELEASE matrix TABLET HYPROMELLOSE acetate SUCCINATE HYDROXYPROPYLCELLULOSE Robust dissolution USP apparatus 3
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基于EVA-BSC的医药制造企业绩效评价研究
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作者 李泽建 李艾琦 《中国物价》 2025年第7期71-76,共6页
医药制造业是我国国民经济的重要组成部分,但受集采扩面、市场竞争加剧等因素影响,部分医药产品利润下滑,企业业绩持续萎靡。本文结合医药制造业的特点、行业战略目标和各利益相关者的诉求,选取财务、外部利益相关者、内部流程、研发创... 医药制造业是我国国民经济的重要组成部分,但受集采扩面、市场竞争加剧等因素影响,部分医药产品利润下滑,企业业绩持续萎靡。本文结合医药制造业的特点、行业战略目标和各利益相关者的诉求,选取财务、外部利益相关者、内部流程、研发创新、学习与成长五个维度,构建基于EVA-BSC的绩效评价体系,对医药制造企业2019-2023年的绩效进行评价。研究发现,医药制造企业存在应收账款周转率低、应付账款周转率低、研发能力不足等问题。对此,本文提出加强应收账款和应付账款管理、合理配置研发人员、建立健全基于EVA-BSC的绩效评价体系等建议。 展开更多
关键词 医药制造业 平衡记分卡(BSC) 经济增加值(eva) 绩效评价
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反应型复合无卤阻燃剂对EVA基复合材料性能的影响 被引量:1
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作者 王平 田洪瑜 +3 位作者 姜越 周意杨 程龙恩 陈龙 《电线电缆》 2025年第3期10-17,共8页
将不饱和磷酸酯齐聚物(unsaturated polyester oligomer,UPEO)与无机阻燃剂复配,制备了反应型复合无卤阻燃剂(OP-FRC),通过熔融共混法将其引入乙烯-醋酸乙烯共聚物(ethylene-vinyl acetate copolymer,EVA)基低烟无卤阻燃线缆护套材料中... 将不饱和磷酸酯齐聚物(unsaturated polyester oligomer,UPEO)与无机阻燃剂复配,制备了反应型复合无卤阻燃剂(OP-FRC),通过熔融共混法将其引入乙烯-醋酸乙烯共聚物(ethylene-vinyl acetate copolymer,EVA)基低烟无卤阻燃线缆护套材料中,采用热重分析仪、差示扫描量热仪、平行板流变仪、电子万能试验机、扫描电子显微镜、极限氧指数测定仪等研究UPEO对复合材料结构和性能的影响。结果表明,OP-FRC中UPEO的引入可以改善无机阻燃剂在EVA基体中的分散性,增强两者间的相互作用,促进无机填料网络的形成,并提高分子链段的运动能力,促进基体缠结结构的松弛,从而改善复合材料的耐疲劳性能、热稳定性和结晶能力。当UPEO质量分数为4%时,复合材料的断裂伸长率为215.5%,疲劳寿命为26354次,极限氧指数为31.5%。 展开更多
关键词 不饱和磷酸酯齐聚物 乙烯-醋酸乙烯酯共聚物 耐疲劳性能 低烟无卤阻燃
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基于绿色EVA视角的化工企业业绩评价研究 被引量:1
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作者 贾永玉 苗蕴慧 《江苏商论》 2025年第1期112-116,共5页
随着十四五规划的推进、“双碳”政策的实施,绿色化工及碳中和将是未来中国重要的经济增长动力之一,化工产业的可持续发展备受关注。本文以中国基础化工行业为研究样本,搜集整理了2020年和2021年相关数据,将绿色EVA值引入化工企业业绩... 随着十四五规划的推进、“双碳”政策的实施,绿色化工及碳中和将是未来中国重要的经济增长动力之一,化工产业的可持续发展备受关注。本文以中国基础化工行业为研究样本,搜集整理了2020年和2021年相关数据,将绿色EVA值引入化工企业业绩评价体系。首先采用因子分析法分别提取各年化工行业业绩表现的主要影响因子,计算因子综合得分;再结合聚类分析对2021年和2020年化工行业业绩表现进行横向分类、纵向对比。以更全面地评价在疫情影响的经济动荡期内化工企业业绩现状、剖析原因并结合化工行业的特点提出相应发展建议。 展开更多
关键词 绿色eva 业绩评价 因子分析 聚类分析
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EVA对DNTF基复合材料性能提升的影响
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作者 金芷妃 辛启超 +3 位作者 王宇利 李媛媛 肖继军 马海霞 《火炸药学报》 北大核心 2025年第12期1110-1120,I0002,共12页
为了提高3,4-二硝基呋咱基氧化呋咱(DNTF)的安全性能,将其与1,1′-二氨基2,2′-二硝基乙烯(FOX-7)以一定质量比和乙烯-醋酸乙烯酯(EVA)复合,制备了DNTF基复合材料。首先,通过分子动力学计算发现DNTF与FOX-7质量比60∶40复合时力学性能最... 为了提高3,4-二硝基呋咱基氧化呋咱(DNTF)的安全性能,将其与1,1′-二氨基2,2′-二硝基乙烯(FOX-7)以一定质量比和乙烯-醋酸乙烯酯(EVA)复合,制备了DNTF基复合材料。首先,通过分子动力学计算发现DNTF与FOX-7质量比60∶40复合时力学性能最优,进一步利用Explo5.0对DNTF和FOX-7(60∶40)的爆速、爆热和爆压进行计算,分别为8753 m/s,-5569 kJ/kg和33.76 GPa,与RDX爆速相当。将二者按照质量比60∶40混合,再将EVA按照质量分数2%、4%、6%、8%、10%进行包覆,制备出DNTF基复合材料。通过扫描电子显微镜(SEM)、X射线粉末衍射仪(XRD)、傅里叶红外光谱仪(FT-IR)、差示扫描量热仪(DSC)、BAM感度测试仪和点火燃烧实验对复合材料的形貌、结构、热分解性能、安全性能和燃烧性能进行了研究。结果表明,在EVA添加质量分数为6%~8%时制备的DNTF基复合材料包覆效果较好,添加质量分数为6%时,DNTF/FOX-7热分解的表观活化能可增加20.01 kJ/mol,特性落高和摩擦能量分别提高20 cm(BAM,5 kg)和36 N以上,提高了炸药的安全性能;且可使DNTF/FOX-7的点火延迟时间提前到36 s以内。 展开更多
关键词 物理化学 FOX-7 3 4-二硝基呋咱基氧化呋咱 DNTF 乙烯-醋酸乙烯酯 eva 机械感度 热分解性能
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An Evaluation of the Mitigating Effects of Α-Tocopherol (Vitamin E) and Ascorbic Acid (Vitamin C) on the Renal Function and Histology of Adult Male Albino Wistar Rats with Sub-Acute Lead Acetate Exposure 被引量:2
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作者 Datonye Dennis Alasia Pedro Chimezie Emem-Chioma Sunday Ogbu Ojeka 《Occupational Diseases and Environmental Medicine》 2020年第2期35-49,共15页
Objectives: The aim of this study was to verify mitigating effects of the antioxidants α tocopherol (Vitamin E) and ascorbic acid (Vitamin C) on lead induced renal toxicity in adult male Wistar rats. Methods: A total... Objectives: The aim of this study was to verify mitigating effects of the antioxidants α tocopherol (Vitamin E) and ascorbic acid (Vitamin C) on lead induced renal toxicity in adult male Wistar rats. Methods: A total of 36 mature male Wistar rats separated into 1 control group fed with rat feeds and water only and 3 study groups fed with 10 mg/ml of lead acetate, 10 mg/ml of lead acetate + 200 mg/2ml of vitamin C and 10 mg/ml of lead acetate + 100 mg/2ml of vitamin E respectively in addition to feds and water for 28 days were used. Blood samples were obtained for renal indices and the kidneys of all rats were harvested, weighed and prepared for histological examination. Result: The percentage weight gain was highest among control rats (20.70%), followed by lead + vitamin E group (18.42%), lead + vitamin C group (17.00%) and the least amongst the lead group (9.50%). The mean serum uric acid of 419.20 ± 35.80 μmol/L in the lead treatment group was significantly higher than 395.50 ± 15.35 μmol/L, 393.30 ± 14.16 μmol/L and 387.67 ± 14.56 μmol/L in the lead + vitamin C group, lead + vitamin E group and controls respectively. The extent and proportion of renal tissue damage was higher in the lead-treated group and the commonest renal abnormalities observed were tubular and interstitial damage seen in 90.00% of rats in the lead-treated group compared to 75.00% and 60.00% in the lead + vitamin C and the lead + vitamin E groups respectively while the control rats had a normal histological appearance. Conclusions: The sub-acute administration of lead acetate may have inhibitory effect on growth of animals, and adversely affect renal function and histology with uric acid as a more reliable marker of lead induced renal toxicity compared to urea and creatinine. The histologic parameters of tubulointerstitial abnormalities were also consistent with lead toxicity. Antioxidants were useful in reducing lead induced renal damage and growth inhibition with vitamin E producing a more potent effect compared to Vitamin C. 展开更多
关键词 Lead acetate Toxicity OXIDATIVE Tissue Stress ANTIOXIDANTS Prevention
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Performance improvement of Ethylene-Vinyl Acetate Copolymer Pour Point Depressant(EVA PPD)by adding small dosages of Laurylamine(LA) 被引量:1
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作者 Xue Xia Chuan-Xian Li +4 位作者 Guang-Yu Sun Ke-Ke Zhao Jie Zhang Bo Yao Fei Yang 《Petroleum Science》 SCIE CAS CSCD 2022年第5期2472-2482,共11页
Lauramine is widely considered to be an asphaltene flocculant,but its effect on the modification of crude oil by PPDs has been little studied.In this paper,the effect of LA dosage on the rheology improvement of EVA PP... Lauramine is widely considered to be an asphaltene flocculant,but its effect on the modification of crude oil by PPDs has been little studied.In this paper,the effect of LA dosage on the rheology improvement of EVA PPDs(100 ppm)on Qinghai waxy crude oil was investigated through rheological measurement,wax precipitating analysis,granularity test and resins/asphaltenes FTIR analysis.Compared with pure EVA,the compounding of LA and EVA obviously enhances the agglomeration degree and reduces the number of fine wax crystals,thus further enhancing the rheology of the oil samples,and the best performance is at the LA dosage of 200 ppm.At relatively small LA dosages,the LA facilitates the adsorption of EVA molecules on the asphaltene surfaces,which favors the becoming of EVA/asphaltenes composite particles;but at relatively high LA dosages,the LA makes the asphaltenes more aggregated and disturbs the EVA adsorption on the asphaltenes,which is adverse for the formation of EVA/asphaltenes compound particles.The compound particles can serve as wax precipitating templates and significantly influence its morphology,thus further improving the crude oil rheology.In consequence,the rheology improvement of EVA PPDs on Qinghai waxy crude oil first increases and then decreases with increasing the LA dosage. 展开更多
关键词 Waxy crude oil eva PPD Laurylamine ASPHALTENES Synergistic effect
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低熔点EVA/POE投料袋对三元乙丙绝热材料性能影响研究
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作者 陈馨 王明超 +2 位作者 吴磊 陈雯 周俊 《宇航材料工艺》 北大核心 2025年第4期63-68,共6页
为减少绝热材料混炼过程中因物料飞扬造成的物料的损失同时降低物料对环境的污染,结合EVA、POE低熔点投料袋可以与原材料一起混炼,在一定量的使用范围内对绝热层混炼胶和硫化胶的性能没有显著影响的特点,研究了低熔点投料袋对EPDM绝热... 为减少绝热材料混炼过程中因物料飞扬造成的物料的损失同时降低物料对环境的污染,结合EVA、POE低熔点投料袋可以与原材料一起混炼,在一定量的使用范围内对绝热层混炼胶和硫化胶的性能没有显著影响的特点,研究了低熔点投料袋对EPDM绝热层力学、烧蚀、硫化性能的影响。测试结果表明,随着EVA或POE材料用量增加,绝热层扭矩差值和硫化速率指数Vc逐渐下降,工艺正硫化时间t90延长,EVA或POE材料并未参与到过氧化物硫化反应。随着POE用量增加,绝热层的拉伸强度和断裂伸长率明显上升,但EVA用量对绝热层力学性能无明显影响。随着POE或EVA材料用量增加,绝热层烧蚀性能无明显变化。 展开更多
关键词 EPDM绝热层 低熔点 eva POE
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