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Uniform Truncation Error for Shannon Sampling Expansion from Local Averages

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Acta Mathematicae Applicatae Sinica 2015年第1期31卷 121-130页

作者： Zhan-jie SONG Pei-xin YE Ping WANG shou-zhen ZENG School of Science and SKL of HESS Tianjin University School of Mathematics and LPMC Nankai University Department of Mathematics School of Science Tianjin University Institute of Mathmatics Zhejiang Wanli University

Let B^pΩ,1≤Р≤∞,be the set of all bounded functions in L^p（R）which can be extended to entire unctions of exponential typeΩ. The unitbrm bounds for truncation error of Shannon sampling expansion fromlocal averages are obtained for functions f∈BpΩwith the decay condition f（t）≤A/t^δ,t≠0,where A and δare positive constants. Furthermore we also establish similar results for non-bandlimit functions in Besov classes with the same decay condition as above.

关键词： Shannon sampling Theorem local averages truncation error modulus of continuity

Enhanced Ultraviolet Resistance of Polypropylene Random Copolymer Filled by ZnO-supported Mesoporous Zeolite

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Chinese Journal of Polymer Science 2015年第7期33卷 976-987页

作者： Mei Li Gu Li Zi-shou Zhang xin Dai Yue-wen Yang 麦堪成 Materials Science Institute School of Chemistry and Chemical Engineering Sun Yat-sen University Key Laboratory for Polymeric Composite and Functional Materials Ministry of Education Guangdong Provincial Key Laboratory for High Performance Polymer-based Composites

To enhance the ultraviolet resistance of ZnO based polymer materials, ZnO-supported mesoporous zeolite（M-ZnO） was prepared and characterized by atomic absorption spectroscopy and scanning electron microscopy. The ultraviolet resistance, crystallization behavior and melting characteristics of ZnO and M-ZnO filled PPR composites were compared by FTIR spectra and differential scanning calorimetry. The ultraviolet resistance of M-ZnO filled PPR composites is higher than that of ZnO filled PPR composites, indicating higher ultraviolet resistance of M-ZnO than that of ZnO. The crystallization temperatures of mesoporous zeolite filled PPR were higher than those of M-ZnO and decreased with increasing UV-irradiation time. But the crystallization temperatures of M-ZnO filled PPR composites were not influenced by UV-irradiation time. The ZnO supported on the surface of zeolite is effective in enhancing the ultraviolet resistance of ZnO based polymer materials.

关键词： Polypropylene random copolymer(PPR) ZnO Mesoporous zeolite Photo-oxidation degradation

Terpenoid Glucosides fromAster Smithianus

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Chemical Research in Chinese Universities 2005年第5期21卷 531-535页

作者： GUO shou-jun ZHAO xin-hua YANG Yong-li CHENG Dong-liang Department of Chemistry National Laboratory of Appied Organic Chemistry Lanzhou University Lanzhou 730000 P. R. China Department of Biology Hanshan Normal University Chaozhou 521041 P. R. China

A diterpenoid trisaccharide, smithoside A, and a saponin, smithoside B, as well as six known compounds, apigenin, apigenin-7-O-glucoside, daucosterol, shanzhiside methyl ester, 8-acetylshanzhiside methyl ester and acteoside, were isolated from Aster smithianus. On the basis of spectral evidence and chemical analytical results, smithosides A and B were identified as pimar-1 5 （ 16 ） -β-ene-8β, 11 α-diol-3β-O-β-D-glucopyranosyl （ 1→3 ） - [ β-glucopyranosyl（ 1 →2 ） ] -β-D-glucopyranoside and 2β,3β, 16β,21β,23-pentahydroxy-12-ene-28 oleanoic acid lactone-3-O-β-D- glucopyranosyl （ 1→3 ） -β-D-glucopyranoside, respectively.

关键词： Aster smithianus Pimarene-type diterpenoid glucoside Triterpenoid glucoside Oleanolic acid lactone

Direct Comparison of Crystal Nucleation Activity of PCL on Patterned Substrates

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Chinese Journal of Polymer Science 2019年第7期37卷 693-699页

作者： Jian Hu Rui xin Chun-Yue Hou shou-Ke Yan Ji-Chun Liu Key Laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-plastics Qingdao University of Science & Technology College of Chemical Engineering and Pharmaceutics Key Laboratory of Polymer Science and Nanotechonology Henan University of Science and Technology

A sample containing different regions with poly(ε-caprolactone)(PCL), oriented polyethylene (PE), and oriented isotactic polypropylene (iPP) films in contact with glass slide has been prepared to be observed in the same view field in an optical microscope and the crystallization of PCL in different regions during cooling from 80 °C down to room temperature at a rate of 1 °C·min^-1 was studied. The results showed that the crystallization of PCL started first at the PE surface and then at the iPP surface, while its bulk crystallization occured much later. This indicates that though both PE and iPP are active in nucleating PCL, the nucleation ability of PE is stronger than that of iPP. This was due to a better lattice matching between PCL and PE than that between PCL and iPP. Moreover, since lattice matching existed between every (hk0) lattice planes of both PCL and PE but only between the (100)PCL and (010)iPP lattice planes, the uniaxial orientation feature of the used PE and iPP films resulted in the existence of much more active nucleation sites of PCL on PE than on iPP. This led to the fact that the nucleation density of PCL at PE surface was so high that the crystallization of PCL at PE surface took place in a way like the film developing process with PCL microcrystallites happened everywhere with crystallization proceeding simultaneously. On the other hand, even though iPP also enhanced the nucleation density of PCL evidently, the crystallization of PCL at iPP surface included still a nucleation and crystal growth processes similar to that of its bulk crystallization.

关键词： Poly(ε-caprolactone) Polypropylene Polyethylene Epitaxy Heterogeneous nucleation

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铝合金后端盖压铸工艺优化及局部挤压设计

铸造 2024年第2期73卷 216-219页

作者：李光浩董超奇卢信学孙宝寿束学道宁波博大机械有限公司浙江宁波315211 宁波大学机械工程与力学学院浙江宁波315211 浙江省零件轧制成形技术研究重点实验室浙江宁波315211

分析了铝合金后端盖铸件结构工艺性,根据压铸工艺经验公式设计了浇注系统。采用Flow-3D软件进行数值模拟,发现后端盖铸件悬置孔区域不能实现金属液顺序充填。根据数值模拟结果修改浇注系统设计并进行实际生产,铸件厚壁区域产生缩孔缺陷... 详细信息

分析了铝合金后端盖铸件结构工艺性,根据压铸工艺经验公式设计了浇注系统。采用Flow-3D软件进行数值模拟,发现后端盖铸件悬置孔区域不能实现金属液顺序充填。根据数值模拟结果修改浇注系统设计并进行实际生产,铸件厚壁区域产生缩孔缺陷。针对厚壁区域设计局部挤压工艺,在其凝固过程中进行挤压补缩,消除了后端盖铸件悬置孔部位缩孔缺陷。

关键词：铝合金压铸后端盖数值模拟工艺优化局部挤压

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钢渣沥青混合料在道路工程中的应用

公路交通科技 2024年第2期41卷 22-38页

作者：惠迎新王欣宇徐新强赵涛宁夏大学土木与水利工程学院宁夏银川750021 宁夏交通建设股份有限公司宁夏银川750001 宁夏交建交通科技研究院有限公司宁夏银川750004

为了总结钢渣在道路工程领域的研究现状,推动钢渣沥青混合料的应用,把握其发展现状并梳理发展需求,综述了国内外钢渣沥青混合料的应用与研究进展。通过对钢渣沥青混合料的制备与施工工艺进行总结分析,围绕钢渣掺量变化,分析其对沥青混... 详细信息

为了总结钢渣在道路工程领域的研究现状,推动钢渣沥青混合料的应用,把握其发展现状并梳理发展需求,综述了国内外钢渣沥青混合料的应用与研究进展。通过对钢渣沥青混合料的制备与施工工艺进行总结分析,围绕钢渣掺量变化,分析其对沥青混合料路用性能的影响,归纳出目前钢渣沥青混合料的优势与不足。最后,分别对钢渣沥青混合料的经济效益、体积膨胀性和环境影响进行综合评估,旨在为钢渣沥青混合料的深入研究与应用提供启示和借鉴。结果表明:钢渣沥青路面具有路用性能优越、服役寿命长、绿色环保等优势,在多个工程实践中得到了验证;在制备钢渣沥青混合料时,级配、原材料种类以及制备工艺的差异均会对混合料性能产生关键影响;在施工过程中,由于钢渣的特殊性,需严格控制运输、摊铺以及碾压阶段的温度与均匀性;钢渣掺量对沥青混合料的路用性能有显著影响,适当掺入钢渣可提升沥青混合料的水稳定性、高温稳定性、抗疲劳性以及抗滑性,但会降低体积稳定性,综合考虑各项指标后建议钢渣适宜掺量范围为40%~50%;在钢渣沥青混合料的推广应用中,应综合评估不同地区的经济效益,并选择合适的钢渣处理工艺,以进一步改善钢渣的应用性能、提高处理效率并降低成本,为工程建设带来更好的灵活性和可持续性。

关键词：道路工程钢渣沥青混合料综合评估钢渣掺量制备与施工路用性能

秀珍菇残次菇超声酶解工艺优化及挥发性风味成分分析

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中国调味品 2024年第7期49卷 24-31页

作者：宋心鹏陈寿辉冯梦媛陈宗忠李怡彬福建师范大学生命科学学院福州350117 福建省农业科学院农产品加工研究所福州350004 福建农林大学金山学院福州350003 福建创新食品科技有限公司福州350101

为提高秀珍菇副产物的附加值,利用秀珍菇残次菇制备调味基料,筛选适宜的蛋白酶酶解秀珍菇残次菇,基于水解度、模糊数学评定法设计单因素试验和响应面法优化超声波耦合蛋白酶酶解的工艺参数,分析酶解产物的抗氧化性和挥发性风味成分。结... 详细信息

为提高秀珍菇副产物的附加值,利用秀珍菇残次菇制备调味基料,筛选适宜的蛋白酶酶解秀珍菇残次菇,基于水解度、模糊数学评定法设计单因素试验和响应面法优化超声波耦合蛋白酶酶解的工艺参数,分析酶解产物的抗氧化性和挥发性风味成分。结果表明,超声酶解最佳工艺条件为料液比1∶30、酶添加量1.5%、pH 7.0、温度47℃、时间72 min、超声功率420 W。在此条件下,秀珍菇水解度、酶解产物得率和综合评分分别为(51.98±3.82)%、(71.83±3.61)%、98.04±3.58;酶解后的总氨基酸含量、抗氧化活性都有显著提高(P<0.05);主要挥发性成分蘑菇醇含量显著增加,月桂烯含量显著减少,且新增了12种挥发性香气成分。该研究结果为秀珍菇残次菇制备调味基料提供了理论和技术支持。

关键词：秀珍菇残次菇酶解液响应面优化抗氧化能力挥发性成分

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罕见高温干旱对杨梅生长影响的研究

江西农业学报 2024年第1期36卷 102-106页

作者：黄新朱寿燕廖必军陈鑫磊韦颖慈溪市气象局浙江慈溪315300 仙居县气象局浙江仙居317300 浙江蓝天气象科技有限公司浙江杭州310017 中国太平洋财产保险股份有限公司宁波分公司浙江宁波315300

分析了浙江省慈溪市2022/2023年度杨梅生育期的温、光、水等气象条件,尤其是2022年盛夏罕见的高温干旱和后续天气对杨梅生长发育的持续影响,结果表明:盛夏罕见的高温干旱不仅会导致杨梅叶片大面积卷曲、萎蔫,以及当年移栽的杨梅幼树大... 详细信息

分析了浙江省慈溪市2022/2023年度杨梅生育期的温、光、水等气象条件,尤其是2022年盛夏罕见的高温干旱和后续天气对杨梅生长发育的持续影响,结果表明:盛夏罕见的高温干旱不仅会导致杨梅叶片大面积卷曲、萎蔫,以及当年移栽的杨梅幼树大量枯死,而且还严重抑制了夏梢的抽发生长和花芽分化;在旱情解除后,秋梢的大量抽发进一步影响了花芽分化和养分积累,导致花芽发育较弱,并形成了大量秋梢果;采收后期若遇高温,秋梢果则会大量变软或脱落。因此,提出了一些能有效防御高温干旱对杨梅影响的对策措施。

关键词：杨梅浙江高温干旱对策生长

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香豆素席夫碱类肼荧光探针的合成及性能研究

化学试剂 2024年第10期46卷 52-57页

作者：孙新峰朱奕妍解晓华盛筱王守信山东第一医科大学研究生院山东济南250117 济宁医学院药学院山东日照276826

以3-(4-氨基苯基)-7-二乙氨基香豆素(ADPC)为荧光母体,碳氮双键为识别位点,构建了一种新型的席夫碱类肼荧光探针HAPC。在V(DMSO)∶V(PBS缓冲液,pH 7.4)=9∶1的体系中,该探针自身荧光微弱,与肼反应后呈现强黄绿色荧光,实现了对肼的Turn-o... 详细信息

以3-(4-氨基苯基)-7-二乙氨基香豆素(ADPC)为荧光母体,碳氮双键为识别位点,构建了一种新型的席夫碱类肼荧光探针HAPC。在V(DMSO)∶V(PBS缓冲液,pH 7.4)=9∶1的体系中,该探针自身荧光微弱,与肼反应后呈现强黄绿色荧光,实现了对肼的Turn-on检测。探针对肼具有良好的选择性与抗干扰能力、较大的斯托克斯位移,检出限低至1.92×10-7 mol/L,检测最适pH范围为3~8。通过HPLC与高分辨质谱验证了HAPC与肼的反应机制。结果表明HAPC与肼经加成-水解-消除反应生成了荧光母体ADPC与对羟基苯腙。此外,探针HAPC能制作成便携式试纸,已成功用于气态肼的检测。

关键词：荧光探针肼香豆素席夫碱合成