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Assessment of densified fuel quality parameters:A case study for wheat straw pellet

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Journal of Bioresources and Bioproducts 2023年第1期8卷 45-58页

作者： Bidhan Nath Guangnan Chen les Bowtell Raid Ahmed Mahmood School of Agriculture and Environmental Science University of Southern QueenslandToowoombaQLD 4350Australia School of Engineering University of Southern QueenslandToowoombaQLD 4350Australia Department of Mechanical Engineering College of EngineeringUniversity of ZakhoZakho 44001Iraq

An investigation was conducted to examine the impact of additive mixing with wheat straw(WS)for pellet *** study manufactured seven types of pellets with different additive combina-tions to evaluate pellet quality characteristics and their relationships.A laboratory-type hammer mill and a pellet mill were used for feedstock preparation and pellet *** investigations showed that the lignin content increased from 7.0%to 13.1%,which was a primary need for ***,the heating value rose from 17.02 to 20.36 MJ/***,the ash content also increased from 7.09%to 16.2%.Results showed that dimension(length and diame-ter),durability,and tensile strength increased significantly with additives while the fines content *** fines content had an inverse relationship with durability and *** straw(60%),together with 10%sawdust(SD),10%corn starch(CS),10%bentonite clay(BC),and 10%biochar(BiC),was optimal with good pellet performance(T7).In addition,both the T5 pellets(70%WS,10%SD,10%BiC,and 10%BC)and the T6 pellets(70%WS,10%SD,10%BiC,and 10%CS)provide suitable quality according to EN plus 2015 standard *** ash content of produced pellet was higher than the recommended value,which suggests that further research onto the alternative additive use for ash reduction is needed.

关键词： Biomass Wheat straw Pellet quality Properties relationship Additive/binding material

Conception and Design of Active Balancer for Planar Mechanisms

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Chinese Journal of Mechanical Engineering 2009年第6期22卷 822-832页

作者： ZHANG Ying YAO Yan-An cha Jianzhong School of Mechanical and Electronic Control Engineering Beijing Jiaotong University Beijing 100044 China

The dynamic balancing is an important issue in mechanism design. For the existing balancing methods, both passive and active ones, there is still room for improvement in adaplability and independency. In view of this, a concept of active balancer is developed as a new solution for the dynamic balancing with more flexibility. The proposed balancer is an independent additional device with a control system inside, which consists of a two-degree-of-freedom （DOF） linkage and a controllable motor, and can be attached to a machine expediently with little change to its original structure and motion. One of the two inputs of the two-DOF linkage shares the same shaft with its output, which is connected to the input shaft of a machine to be balanced and driven by the original actuator. The other input is driven by the control motor. By properly selecting the speed trajectories of the control motor and link parameters of the two-DOF linkage, one or more dynamic effects of the mechanisms can be minimized or eliminated adaptively. The design procedure of the active balancer is put forward and a two-step optimization is developed to find out optimal design parameters of the balancer for various design requirements and constraints. Taking a force-balanced crank-rocker mechanism as the reference mechanism, numerical examples are given to illustrate the design procedure. The balancing effects of the proposed balancer are compared with those of the existing adding dyads （DYAD） method. The results show that the introduction of the control system provides the active balancer with better balancing effect and more flexibility than the DYAD method. A considerable reduction in the dynamic effects （input torque, shaking moment and shaking force） can be achieved for different balancing object by designing the structural and control parameters of the balancer, and the deterioration of dynamic performance caused by alterative working conditions can be compensated effectively by redesigning the

关键词： active balancing shaking moment input torque shaking force optimum balancing two-degree-of-freedom linkage

Variations in dynamic recrystallization behavior and mechanical properties of AZ31 alloy with extrusion temperature

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镁合金学报(英文) 2023年第7期11卷 2351-2365页

作者： Jae Won cha Sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea

This study investigates the effects of extrusion temperature on the dynamic recrystallization(DRX)behavior of a Mg-3Al-1Zn-0.3Mn(AZ31,wt%)alloy during hot extrusion and on the microstructural characteristics and mechanical properties of materials extruded at 350 and 450℃.An increase in the extrusion temperature causes a decrease in the amount of strain energy accumulated in the material during extrusion,because of promoted activation of pyramidalslip and dynamic *** reduced strain energy weakens the DRX behavior during extrusion,which eventually results in a decrease in the area fraction of recrystallized grains of the extruded *** material extruded at 450℃has coarser grains and a stronger basal fiber texture than that extruded at 350℃.As the extrusion temperature increases from 350 to 450℃,the tensile yield strength(TYS)of the extruded material increases from 191.8 to 201.5 MPa,whereas its compressive yield strength(CYS)decreases from 122.5 to 111.0 MPa;consequently,its tension-compression yield stress ratio(CYS/TYS)decreases from 0.64 to *** increase in the TYS is attributed mainly to the stronger texture hardening and strain hardening effects of the extruded material,and the decrease in the CYS is attributed to the reduced twinning stress resulting from grain coarsening and texture *** microstructural and textural evolutions of the materials during extrusion and the deformation and hardening mechanisms of the extruded materials are discussed in detail.

关键词： Mg-Al-Zn alloy Extrusion Dynamic recrystallization Microstructure Yield asymmetry

屈螺酮炔雌醇复合片治疗多囊卵巢综合征的有效性和安全性分析

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实用妇科内分泌电子杂志 2024年第13期11卷 56-59页

作者：雷琼查良英苏州高新区人民医院药剂科江苏苏州215129

目的探讨屈螺酮炔雌醇复合片治疗多囊卵巢综合征的有效性和安全性。方法选取本院收治的116例多囊卵巢综合征患者为研究对象,随机分为两组,各58例。对照组使用炔雌醇环丙孕酮片治疗,试验组使用屈螺酮炔雌醇复合片治疗,比较两组的治疗... 详细信息

目的探讨屈螺酮炔雌醇复合片治疗多囊卵巢综合征的有效性和安全性。方法选取本院收治的116例多囊卵巢综合征患者为研究对象,随机分为两组,各58例。对照组使用炔雌醇环丙孕酮片治疗,试验组使用屈螺酮炔雌醇复合片治疗,比较两组的治疗效果。结果试验组治疗总有效率为93.1%,高于对照组的79.3%(P<0.05);试验组不良反应发生率为3.4%,低于对照组的13.8%(P<0.05);治疗后,试验组黄体生成素、卵泡刺激素、空腹胰岛素、胰岛素抵抗指数、总胆固醇、三酰甘油水平低于对照组(P<0.05)。结论屈螺酮炔雌醇复合片治疗多囊卵巢综合征疗效显著,安全性高,可有效改善患者的性激素水平,降低对患者糖脂代谢的影响,可推广使用。

关键词：屈螺酮炔雌醇复合片多囊卵巢综合征有效性安全性

Posterior propriety in nonparametric mixed efects model

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Applied Mathematics(A Journal of Chinese Universities) 2013年第3期28卷 369-378页

作者： XU An-cha TANG Yin-cai College of Mathematics and Information Science Wenzhou University School of Finance and Statistics East China Normal University

It is well known that spline smoothing estimator relates to the Bayesian estimate under partially informative normal prior. In this paper, we derive the conditions for the pro- priety of the posterior in the nonparametric mixed effects model under this class of partially informative normal prior for fixed effect with inverse gamma priors on the variance compo- nents and hierarchical priors for covariance matrix of random effect, then we explore the Gibbs sampling procedure.

关键词： nonparametric mixed effect model Bayesian spline smoothing Gibbs sampling.

Anti-aging properties of Ribes fasciculatum in Caenorhabditis elegans

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Chinese Journal of Natural Medicines 2016年第5期14卷 335-342页

作者： Hoon Jeon Dong Seok cha Department of Oriental Pharmacy College of Pharmacy Woosuk University

The present study investigated the effects and underlying mechanism of ethylacetate fraction of Ribes fasciculatum （ERF） on the lifespan and stress tolerance using a Caenorhabditis elegans model. The longevity activity of ERF was determined by lifespan assay under normal culture condition. The survival rate of nematodes under various stress conditions was assessed to validate the effects of ERF on the stress tolerance. To determine the antioxidant potential of ERF, the superoxide dismutase （SOD） activities and intracellular reactive oxygen species （ROS） levels were investigated. The ERF-mediated change in SOD-3 expression was examined using GFP-expressing transgenic strain. The effects of ERF on the aging-related factors were investigated by reproduction assay and pharyngeal pumping assay. The intestinal lipofuscin levels of aged nematodes were also measured. The mechanistic studies were performed using selected mutant strains. Our results indicated that ERF showed potent lifespan extension effects on the wild-type nematode under both normal and various stress conditions. The ERF treatment also enhanced the activity and expression of superoxide dismutase （SOD） and attenuated the intracellular ROS levels. Moreover, ERF-fed nematodes showed decreased lipofuscin accumulation, indicating ERF might affect age-associated changes in C. elegans. The results of mechanistic studies indicated that there was no significant lifespan extension in ERF-treated daf-2, age-l, sir-2.1, and daf-16 null mutants, suggesting that they were involved in ERF-mediated lifespan regulation. In conclusion, R. fasciculatum confers increased longevity and stress resistance in C. elegans via SIR-2.1-mediated DAF-16 activation, dependent on the insulin/1GF signaling pathway.

关键词： Ribesfasciculatum Lifespan Aging Stress tolerance Caenorhabditis elegans

Proline Accumulation,Photosynthetic Abilities and Growth characters of Sugarcane(Saccharum officinarum L.) Plantlets in Response to Iso-Osmotic Salt and Water-Deficit Stress

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Agricultural Sciences in China 2009年第1期8卷 51-58页

作者： Suriyan cha-um chalermpol Kirdmanee National Center for Genetic Engineering and Biotechnology(BIOTEC) National Science and Technology Development Agency(NSTDA)

The aim of this study was to investigate the biochemical, physiological and morphological responses of sugarcane to iso- osmotic salt and water-deficit stress. Disease-free sugarcane plantlets derived from meristem cuttings were photo- autotrophically grown in MS media and subsequently exposed to -0.23 （control）, -0.67 or -1.20 MPa iso-osmotic NaCl （salt stress） or mannitol （water-deficit stress）. Chlorophyll a （Chl a）, chlorophyll b （Chl b）, total carotenoids （Cx＋c）, maximum quantum yield of PSII （Fv/Fm）, photon yield of PSII （ΦPSII）, stomatal conductance （Gs） and transpiration rate （E） in the stressed plantlets were significantly reduced when compared to those of plantlets of the control group （without mannitol or NaCl）, leading to net-photosynthetic rate （Pn） and growth reduction with positive correlation. In addition, physiological changes and growth parameters of plantlets in the salt stress conditions were more sharply reduced than those in waterdeficit stress conditions. On the other hand, the proline content and non-photochemical quenching （NPQ） in the leaves of stressed plantlets increased significantly, especially in response to iso-osmotic salt stress. The chlorophyll pigments in iso-osmotic stressed leaves were significantly degraded （r^2 = 0.93）, related to low water oxidation （r^2 = 0.87）, low net- photosynthetic rate （r^2 = 0.81）, and growth reduction （r^2 = 0.97）. The multivariate biochemical, physiological and growth parameters in the present study should be further used to develop salt, or drought, tolerance indices in sugarcane breeding programs.

关键词： growth performances net-photosynthetic rate pigment degradation proline water oxidation

含粗骨料尾砂膏体长距离管输流变特性及阻力预测

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哈尔滨工程大学学报 2024年第3期45卷 535-542页

作者：王小林严庆文王洪江尹升华茶强华熊有为北京科技大学土木与资源工程学院北京100083 西安建筑科技大学资源工程学院陕西西安710055 云南驰宏锌锗股份有限公司会泽矿业分公司云南曲靖655000 长沙有色冶金设计研究院有限公司湖南长沙410000

为探明质量浓度、粗骨料含量、灰砂质量比和水化时间对膏体长距离管输流变特性的影响,本文基于正交设计开展流变实验,采用回归分析建立流变参数预测模型,在此基础上通过理论推导建立管道阻力预测模型,采用现场实测数据验证阻力预测结果... 详细信息

为探明质量浓度、粗骨料含量、灰砂质量比和水化时间对膏体长距离管输流变特性的影响,本文基于正交设计开展流变实验,采用回归分析建立流变参数预测模型,在此基础上通过理论推导建立管道阻力预测模型,采用现场实测数据验证阻力预测结果的可靠性。结果表明:含粗骨料尾砂膏体属于宾汉流体,质量浓度和粗骨料含量对膏体流变参数的影响最显著;屈服应力随质量浓度的增大呈指数增长,随粗骨料含量的增加呈指数减小,随水化时间的增加呈线性增长,与灰砂质量比的关系不大;塑性粘度随质量浓度的增大呈指数增长,随粗骨料含量的增加呈线性减小,随灰砂质量比和水化时间的增加呈线性增长;建立的流变参数预测模型平均误差小于4.3%,基于宾汉流变模型建立的管道阻力模型预测值比现场实测值偏大12.5%,满足工程应用的精度要求。

关键词：尾砂膏体粗骨料长距离输送流变特性演化规律管道阻力流变参数预测阻力预测

circ_UBE2C通过调控miR-107/HK2分子轴促进肺癌细胞增殖和糖酵解

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陆军军医大学学报 2024年第15期46卷 1729-1739页

作者：聂霁刘晨普丹丹查梅张云辉云南省第一人民医院昆明理工大学附属医院呼吸与危重症医学科昆明650032 昆明理工大学医学院昆明650093

目的探讨circ_UBE2C对肺癌细胞增殖和糖酵解的影响及其作用机制。方法基于TCGA数据库分析circ_UBE2C、miR-107和己糖激酶2(hexokinase 2,HK2)在肺癌组织和正常肺组织中的表达情况。采用Kaplan-Meier法绘制生存曲线,分析circ_UBE2C/miR-1... 详细信息

目的探讨circ_UBE2C对肺癌细胞增殖和糖酵解的影响及其作用机制。方法基于TCGA数据库分析circ_UBE2C、miR-107和己糖激酶2(hexokinase 2,HK2)在肺癌组织和正常肺组织中的表达情况。采用Kaplan-Meier法绘制生存曲线,分析circ_UBE2C/miR-107/HK2表达量和肺癌患者生存期的相关性。常规培养人正常肺上皮细胞(BEAS-2B)和人肺癌细胞株(A549、NCI-H460和NCI-H1299),采用qRT-PCR检测circ_UBE2C和miR-107的表达量,Western blot检测HK2和PCNA蛋白的表达量。将A549和NCI-H1299细胞分为空白组(NC)、circ_UBE2C敲减组(si-circ)、HK2敲减组(si-HK2)、同时敲减miR-107+HK2组(miR-inhibitor+si-HK2)和同时敲减circ_UBE2C+miR-107组(si-circ+miR-inhibitor)。CCK-8和克隆形成实验分析细胞增殖活力。葡萄糖摄取比色测定试剂盒、乳酸检测试剂盒和ATP含量测定试剂盒分析A549和NCI-H1299细胞葡萄糖摄取量、乳酸生成量和ATP产生量。Seahorse XF糖酵解应激测试试剂盒和Seahorse XF细胞线粒体应激测试试剂盒检测细胞外酸化率(extracellular acidification ratio,ECAR)和细胞耗氧率(oxygen consumption ratio,OCR)。双荧光素酶报告基因实验评估circ_UBE2C和miR-107、miR-107和HK2的靶向关系。结果与正常组织相比,肺癌组织中circ_UBE2C和HK2表达上调,miR-107表达下调(P<0.05)。与BEAS-2B细胞相比,A549和NCI-H1299细胞中circ_UBE2C和HK2表达量升高,miR-107表达下调(P<0.05)。生存分析显示,circ_UBE2C和HK2高表达或miR-107低表达肺癌患者的生存期较短(P<0.05)。相比于NC组,si-circ或si-HK2组A549和NCI-H1299细胞增殖活力、葡萄糖摄取量、乳酸生成量、ATP产生量、ECAR和OCR均显著减少(P<0.05)。双荧光素酶报告基因证实,circ_UBE2C靶向负调控miR-107,且HK2是miR-107的靶基因。与si-HK2组相比,miR-inhibitor+si-HK2组和si-circ+miR-inhibitor组中A549和NCI-H1299细胞增殖活力和糖酵解水平显著增加。结论敲减circ_UBE2C可显著抑制肺癌细胞增殖和糖酵解水平,其机制是通过靶向上调miR-107抑制HK2表达。

关键词：肺癌 circ_UBE2C/miR-107/HK2分子轴 Warburg效应增殖