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Applied Mathematics and Mechanics(English Edition) 2023年第8期44卷 1317-1330页

作者： Yijin ZHANG Bin LIU Fei PENG heran JIA Zeang ZHAO Shengyu DUAN Panding WANG Hongshuai LEI Beijing Key Laboratory of Lightweight Multi-functional Composite Materials and Structures Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

The Schwarz primitive triply periodic minimal surface(P-type TPMS)lattice structures are widely ***,these lattice structures have weak load-bearing capacity compared with other cellular *** this paper,an adaptive enhancement design method based on the non-uniform stress distribution in structures with uniform thickness is proposed to design the P-type TPMS lattice structures with higher mechanical *** types of structures are designed by adjusting the adaptive thickness distribution in the *** keeps the same relative density,and the other keeps the same of non-enhanced region *** with the uniform lattice structure,the elastic modulus for the structure with the same relative density increases by more than 17%,and the yield strength increases by more than 10.2%.Three kinds of TPMS lattice structures are fabricated by laser powder bed fusion(L-PBF)with 316L stainless steel to verify the proposed enhanced *** manufacture-induced geometric deviation between the as-design and as-printed models is measured by micro X-ray computed tomography(μ-CT)*** quasi-static compression experimental results of P-type TPMS lattice structures show that the reinforced structures have stronger elastic moduli,ultimate strengths,and energy absorption capabilities than the homogeneous P-TPMS lattice structure.

关键词： additive manufacturing(AM) triply periodic minimal surface(TPMS) enhanced design model mechanical property micro X-ray computed tomography(u-CT)

Regional Distribution and Prospects of Potash in China

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Acta Geologica Sinica(English Edition) 2011年第1期85卷 17-50页

作者： ZHENG Mianping ZHANG Yongsheng YUAN heran LIU Xifang CHEN Wenxi LI Jinsuo R＆D Center for Saline Lake and Epithermal Deposit Chinese Academy of Geological Sciences Key Laboratory of Saline Lake Resources and Environment Ministry of Land and Resources Beijing 100037

China was formed by amalgamation of several small continental blocks （cratons）, micro, blocks and orogenic belts in different paleoclimatic settings. It may be correlated with other continental blocks but has its own specific characteristics; therefore the tectonic environments of China＇s marine and continental saline basins and salt, and potash, forming environment have some specific characteristics： multiple phases of salt formation, difference in salt, forming ages, migration and concentration of salt, forming processes and diversity of component materials, as well as small sizes of marine saline basins and great changes of saline basins in the late stage and occurrence of abundant liquid mineral resources. The nature of the tectonic basement exerted a key controlling effect on the formation of potash basins. The stable tectonic region was favorable for potash concentration in a quasi, stable region, and quasi, and the quasi-stable region was favorable for salt concentration and potash formation in a local stable tectonic region. Most China＇s major ancient saline basins occur in ＂quasi, cratons （continental block）＂; especially all the marine saline basins occur in continental blocks with the Precambrian basement. These regions are the key ones for potash search. Most relatively large, scale soluble salt deposits are developed in relatively stable continental nuclei. According to the characteristics of the tectonic domains where China＇s salt, forming basins are located, the North China, Yangtze and Tarim, Qaidam salt minerogenetic domains and the northern Qiangtang, western Yunnan salt minerogenetic belt may be distinguished. Their salt and potash prospects will be discussed separately.

关键词： regional analysis of potash structural basement-controlled potash formation specific saltand potash-forming characteristics salt minerogenetic domain potash prospects

Energy status regulated umami compound metabolism in harvested shiitake mushrooms(Lentinus edodes)with spores triggered to release

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Food Science and Human Wellness 2023年第1期12卷 303-311页

作者： Rongrong Xia Xuemei Zhao Guang Xin Libin Sun heran Xu Zhenshan Hou Yunting Li Yafei Wang College of Food Science Shenyang Agricultural UniversityShenyang 110866China Sichuan national inspection and Testing Co. Ltd.Luzhou 646000China

The molecular mechanisms of energy status related to the umami taste of postharvest shiitake mushrooms during spore release remain poorly *** this study,the variations of energy status and umami taste of mushrooms were measured at 25℃.At 24 h storage,slight spore prints of mushrooms were first pictured,respiration *** ATP decrease and ADP increase were also observed as the initiation of postharvest senescence(P<0.05).Meanwhile,the activities of phosphohexose isomerase,succinate dehydrogenase,glucose-6-phosphate dehydrogenase and cytochrome c oxidase and the contents of umami nucleotides and amino acids were maintained at higher levels in mushrooms with spore ***,the equivalent umami concentration(EUC)was strongly correlated with energy levels(R=0.80).Fifteen related gene expression levels in the energy metabolism pathway were ***1 and LeAK were significantly expressed in the conversion of ATP into AMP and played key roles in connecting the energy state and umami *** results provided valuable insights on the umami taste associated with energy metabolism mechanism during postharvest mushroom spore release.

关键词： Shiitake mushrooms Spore release Energy metabolism Umami taste Transcriptome

共混改性聚乳酸基薄膜的制备及其包膜肥的缓释性能研究

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生物化工 2024年第2期10卷 83-88页

作者：王聪莹王丽敏石宏岩崔佳欣周赫然赤峰学院资源环境与建筑工程学院内蒙古赤峰024000 赤峰学院化学与生命科学学院内蒙古赤峰024000

以二氯甲烷(DCM)或无水乙醇(EtOH)为溶剂,以聚乳酸(PLA)为原料,通过与聚乙二醇(PEG)、聚丁二酸丁二醇酯(PBS)共混改性制备生物可降解聚合物膜。同时将生物质灰渣与尿素混掺制备球状肥芯,通过高压喷雾包覆10%聚合物膜制备包膜肥颗粒。通... 详细信息

以二氯甲烷(DCM)或无水乙醇(EtOH)为溶剂,以聚乳酸(PLA)为原料,通过与聚乙二醇(PEG)、聚丁二酸丁二醇酯(PBS)共混改性制备生物可降解聚合物膜。同时将生物质灰渣与尿素混掺制备球状肥芯,通过高压喷雾包覆10%聚合物膜制备包膜肥颗粒。通过氮素渗透率测试和静水中肥料颗粒氮素渗透实验确定聚合物膜及包膜肥的尿素释放能力。结果表明,以DCM为溶剂,将PLA和PBS共混制备得到的聚合物膜表面结构致密、力学性能与疏水性相对于PLA膜明显提高;以其制备的包膜肥对氮素溶液的渗透系数小,在第1天和第28天的氮素释放率分别为0.27%和40.05%,缓释周期较长。

关键词：包膜肥缓释肥生物可降解膜

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数控机床直线进给轴温度测点优化研究

制造技术与机床 2024年第2期 147-151页

作者：崔展华杨赫然孙兴伟赵泓荀穆士博张维锋沈阳工业大学机械工程学院辽宁沈阳110870 辽宁省复杂曲面数控制造技术重点实验室辽宁沈阳110870

为分析数控机床直线进给系统的温度场,需要布置一定数量的温度测点来进行温度数据的采集。然而,测点的位置和数目都会对研究结果产生直接影响。为实现准确布置温度测点,文章提出一种基于统计学理论进行改进的Canopy-FCM-GRA温度测点优... 详细信息

为分析数控机床直线进给系统的温度场,需要布置一定数量的温度测点来进行温度数据的采集。然而,测点的位置和数目都会对研究结果产生直接影响。为实现准确布置温度测点,文章提出一种基于统计学理论进行改进的Canopy-FCM-GRA温度测点优化模型。以某数控机床X向直线进给轴为例,首先根据测得的实验数据确定预聚类数,然后通过模糊矩阵和灰色关联度系数筛选出相应的温度敏感点,最后基于SVR理论分别建立温度测点优化前和优化后的温度-热误差预测模型,通过比较两个模型精度来验证温度测点优化的有效性。结果表明,温度测点优化效果良好,通过优化后的测温点可准确探究进给系统的热特性。

关键词：直线进给轴改进算法温度测点优化建模精度

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三维微流控芯片的挤出式3D打印工艺

微纳电子技术 2024年第9期61卷 125-132页

作者：韩蕴达苑泽伟郭凯郑雄飞王赫然沈阳工业大学机械工程学院沈阳110870 中国科学院沈阳自动化研究所机器人学国家重点实验室沈阳110016 中国科学院机器人与智能制造创新研究院沈阳110169

微流控芯片技术在疾病模型、药物筛选和个性化医疗领域显示出巨大的应用潜力。针对传统二维微流控芯片在模拟复杂生物环境方面存在局限性的问题,开发了一种新型的适用于挤出式3D打印的高分子共混材料,该混合材料由聚L-丙交酯-己内酯(PL... 详细信息

微流控芯片技术在疾病模型、药物筛选和个性化医疗领域显示出巨大的应用潜力。针对传统二维微流控芯片在模拟复杂生物环境方面存在局限性的问题,开发了一种新型的适用于挤出式3D打印的高分子共混材料,该混合材料由聚L-丙交酯-己内酯(PLCL)和聚乙二醇(PEG)组成。测试了PLCL和PEG质量比分别为7∶3、6∶4、5∶5的三种混合材料的流变性能,筛选最佳配比材料,优化打印工艺参数,实现了复杂三维结构的高精度打印,并且打印件具备明显的抗塌陷能力和飞线断丝的可控性。提出了一种创新的微流控芯片分区设计与打印方法,将芯片结构分为4个区域并单独优化打印轨迹,有效减少了悬空结构产生的塌陷。实验结果显示,PLCL和PEG质量比为7∶3的混合材料具有良好的可打印性能,在3 mm/s的打印速度、20 mm/s的飞线速度下,成功实现了无需溶芯材料的三维微流控芯片的打印,微通道截面显示了良好的形状。细胞实验显示,PLCL/PEG材料支架对人脐静脉内皮细胞(HUVEC)具有良好的细胞相容性,并且具有调节巨噬细胞极化、促进M2型表型形成的能力,显示了其在抗炎和免疫调节方面的功能。研究结果为微流控芯片的制造提供了新的材料和制备技术,拓展了3D打印在生物医学领域的应用范围,并为未来器官芯片技术的临床转化提供了实验基础。

关键词：微流控芯片挤出式3D打印高分子共混材料细胞相容性免疫调节

黄芪多糖对H22荷瘤小鼠PD-1抑制剂抗癌能力的影响

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中国中医药科技 2024年第2期31卷 217-222页

作者：林泽晨周河燃钟亚珍陆金华王珏杭州市中医院浙江杭州310007

目的:以H22荷瘤小鼠为模型,观察黄芪多糖(APS)对PD-1抑制剂抗癌能力的增强效果并探讨其机制。方法:建立H22荷瘤小鼠模型,分别给予PD-1抑制剂和/或不同浓度APS处理,记录肿瘤生长情况,ELISA法检测肿瘤坏死因子(TNF-α)、白介素1β(IL-1β... 详细信息

目的:以H22荷瘤小鼠为模型,观察黄芪多糖(APS)对PD-1抑制剂抗癌能力的增强效果并探讨其机制。方法:建立H22荷瘤小鼠模型,分别给予PD-1抑制剂和/或不同浓度APS处理,记录肿瘤生长情况,ELISA法检测肿瘤坏死因子(TNF-α)、白介素1β(IL-1β)、白介素2(IL-2)、干扰素γ(IFN-γ)、白介素4(IL-4)、白介素10(IL-10)、转化生长因子(TGF-β)等血浆细胞因子浓度,Western Blot法检测肿瘤及脾脏组织PD-1表达,流式细胞术检测肿瘤浸润细胞类型。结果:(1)APS及PD-1抑制剂均能抑制H22荷瘤小鼠的肿瘤生长,联合用药效果更为显著,且抑制强度随APS浓度上升而增加。(2)APS联合PD-1抑制剂作用后,血浆TNF-α、IL-1β、IFN-γ、IL-10、TGF-β浓度上升,IL-2、IL-4血浆浓度下降,肿瘤及脾脏组织PD-1蛋白表达下降,肿瘤组织CD_(4)^(+)CD-8细胞和CD_(4)^(+)CD_(8)^(+)细胞浸润比例增加。结论:APS能增强PD-1抑制剂抗H22肝癌能力,可能与调节细胞因子分泌、抑制PD-1表达、增加肿瘤组织淋巴细胞浸润相关。

关键词：黄芪多糖免疫检查点肝细胞癌肿瘤生长细胞因子 PD-1蛋白小鼠

孤独症谱系障碍患者脑区功能复杂度变化及其与预测脑龄的关系

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中国医学影像技术 2024年第9期40卷 1319-1322页

作者：孟天姿李赫冉刘姝婷刘喆王颖囡吕睿赵海辰张光玉何乐民张瑱蔡小涛山东第一医科大学(山东省医学科学院)放射学院山东泰安271016

目的观察孤独症谱系障碍(ASD)患者脑区功能复杂度变化及其与预测脑龄的关系。方法下载93例ASD患者及96名正常发育青少年(健康人)脑静息态功能MRI(rs-fMRI)公开数据,利用自行研制的虚拟数字脑软件提取脑区功能复杂度;分析ASD患者脑区功... 详细信息

目的观察孤独症谱系障碍(ASD)患者脑区功能复杂度变化及其与预测脑龄的关系。方法下载93例ASD患者及96名正常发育青少年(健康人)脑静息态功能MRI(rs-fMRI)公开数据,利用自行研制的虚拟数字脑软件提取脑区功能复杂度;分析ASD患者脑区功能复杂度改变及其与年龄的相关性。分别以65例ASD患者及67名健康人为训练集训练2个预测脑龄网络,以另28例ASD患者及29名健康人为测试集预测脑龄并比较预测误差。结果相比健康人,ASD患者自动解剖标记(AAL)模板中的左侧楔前叶、左侧楔叶和右侧海马旁回基于香农熵的功能复杂度明显减弱而左侧楔叶和右侧小脑CrusⅡ区基于排列熵的功能复杂度明显增强;左侧海马基于Pearson相关系数的功能复杂度减弱而左侧颞中叶基于Pearson相关系数的功能复杂度增强。ASD患者脑区功能复杂度与年龄的相关性有限(|r|均<0.4)。以训练后全连接网络预测测试集ASD患者及健康人的脑龄均低于实际年龄,但二者预测误差差异无统计学意义(P=0.283)。结论ASD患者部分脑区功能存在功能复杂度改变;基于所获全连接网络预测的ASD患者脑龄偏低,但其脑区功能复杂度变化对此无显著影响。

关键词：孤独症谱系障碍磁共振成像脑

维普期刊数据库博看期刊

D-二聚体水平与晚期非小细胞肺癌血瘀证及其亚型分布的相关性研究

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中国中医药科技 2024年第2期31卷 191-195,199页

作者：周河燃黄挺杨雪飞张志娣郭俊华浙江中医药大学附属杭州市中医院浙江杭州310007

目的:初步探寻晚期肺癌患者D-二聚体水平与中医血瘀证及其亚型的分布规律。方法:收集杭州市中医院、杭州市丁桥医院肿瘤科及胸外科2020年9月—2022年8月住院治疗的晚期非小细胞肺癌患者的中医四诊、血浆D-二聚体等资料,初步探寻此类患... 详细信息

目的:初步探寻晚期肺癌患者D-二聚体水平与中医血瘀证及其亚型的分布规律。方法:收集杭州市中医院、杭州市丁桥医院肿瘤科及胸外科2020年9月—2022年8月住院治疗的晚期非小细胞肺癌患者的中医四诊、血浆D-二聚体等资料,初步探寻此类患者D-二聚体水平与中医血瘀证及其亚型的分布规律。结果:化疗、靶向治疗前后,D-二聚体正常者血瘀证出现频率分别仅为24.5%、28.6%,D-二聚体升高患者血瘀证出现频率高达87.2%、88.3%;治疗前D-二聚体轻度升高与显著升高两者血瘀证亚型分布相同,出现频率高低依次皆为气虚证、阴虚证、痰浊证、气滞证、血热证,但随着D-二聚体水平升高,痰浊证、气滞证频率则显著增加;化疗后D-二聚体轻度升高与显著升高两者血瘀证亚型分布皆以阴虚证、气滞证、气虚证为主;靶向治疗后D-二聚体轻度升高与显著升高两者血瘀证亚型分布则以阴虚证、血热证、气虚证为主。结论:血瘀证是晚期非小细胞肺癌常见的证候,D-二聚体水平与中医血瘀证密切相关,D-二聚体水平越高,中医血瘀证出现频率亦越高。化疗、靶向治疗不影响患者血瘀证总体证型分布,但影响血瘀证的亚型分布。血瘀证亚型总体分布虚证以气虚证、阴虚证为主,实证以痰浊证、气滞证为主。气虚血瘀证、阴虚血瘀证是贯穿晚期非小细胞肺癌综合治疗的主导证型,但靶向治疗后需重视血热血瘀证;对此开展针对性有效干预,灵活、精准运用活血化瘀疗法。

关键词：晚期非小细胞肺癌血瘀证血瘀证亚型 D-二聚体相关性

Comprehensive evaluation of Actinidia arguta fruit based on the nutrition and taste:67 germplasm native to Northeast China

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Food Science and Human Wellness 2022年第2期11卷 393-404页

作者： Mengting Song heran Xu Guang Xin Changjiang Liu Xiaorong Sun Yinhong Zhi Bin Li Yixiao Shen College of Food Science Shenyang Agricultural UniversityShenyang 110866China

Actinidia arguta is a berry fruit with high nutritional *** evaluate the comprehensive quality,the fruit weight,titratable acid(TAC),soluble solids(SSC),vitamin C,mineral elements,and taste value of67 accessions of *** were measured,and sensory attributes including olfactive intensity,juiciness,sweetness,sourness,and astringency were *** analysis was carried out based on mineral elements,and principal component analysis(PCA)was used for comprehensive score *** result demonstrated that fruit weight ranged from 3.5 g to 24.2 g,SSC ranged from 11.94%to 20.56%,TAC ranged from 0.15%to 1.20%,and vitamin C ranged from 3.51 g/kg to 230.76 g/kg(fresh weight)among the tested *** were significant differences in sourness,sweetness,bitterness,and umami among the 67 accessions based on electronic tongue analysis,and this result was rapidly and objectively characterized by the sensory *** dendrogram was obtained and clustered the accessions into two major clusters,and five principal components were extracted by ***,the information provided by this study identified the 10 best germplasm resources for fresh-eating and processing *** can provide theoretical reference for nutritional efficacy evaluation and food development of ***.

关键词： Actinidia arguta Electronic tongue analysis Cluster analysis Principal component analysis Comprehensive quality