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International Journal of Mining Science and Technology 2016年第4期26卷 645-652页

作者： Jiang Bangyou Wang Lianguo Lu Yinlong Sun Xiaokang jin gan State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology Xuzhou 221008 China

To investigate the abnormal ground pressures and roof control problem in fully mechanized repeated mining of residual coal after room and pillar mining, the roof fracture structural model and mechanical model were developed using numerical simulation and theoretical analysis. The roof fracture characteristics of a repeated mining face were revealed and the ground pressure law and roof supporting condi- tions of the repeated mining face were obtained. The results indicate that when the repeated mining face passes the residual pillars, the sudden instability causes fracturing in the main roof above the old goal and forms an extra-large rock block above the mining face. A relatively stable ＂Voussoir beam＂ structure is formed after the advance fracturing of the main roof. When the repeated mining face passes the old goaf, as the large rock block revolves and touches gangue, the rock block will break secondarily under overburden rock loads. An example calculation was performed involving an integrated mine in Shanxi province, results showed that minimum working resistance values of support determined to be reason- able were respectively 11,412 kN and 10,743 kN when repeated mining face passed through residual pillar and goaf. On-site ground pressure monitoring results indicated that the mechanical model and support resistance calculation were reasonable.

关键词： Residual coal after room and pillar mining Repeated mining Fully mechanized caving face Roof control Support resistance

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基础地理实体数据库应用管理系统设计与实现

城市勘测 2024年第2期 17-22页

作者：甘斌方登茂金鑫李蕊娟西安市勘察测绘院陕西西安710054 吉奥时空信息技术有限公司湖北武汉430223

以高效服务城市管理和城市治理为导向,根据自然资源管理和城市信息化发展新需求,结合国家新型基础测绘试点,提出了满足行业应用需求的基础地理实体分类和数据组织模式,设计并建设了基础地理实体数据库及其应用管理系统,解决了地理实体... 详细信息

以高效服务城市管理和城市治理为导向,根据自然资源管理和城市信息化发展新需求,结合国家新型基础测绘试点,提出了满足行业应用需求的基础地理实体分类和数据组织模式,设计并建设了基础地理实体数据库及其应用管理系统,解决了地理实体数据汇聚、存储、管理、按需组装等问题,打通了多源异构时空数据管理与应用的壁垒,有力支撑了实景三维西安建设,提升了基础测绘的有效供给能力,为实景三维中国建设提供了借鉴和参考。

关键词：基础地理实体数据库应用管理系统实景三维

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生物增效技术在工业园区污水处理厂的应用

中国给水排水 2024年第16期40卷 121-125页

作者：丁来保田庆文盘爱享杨然郭奇朱津苇房桂干中国林业科学研究院林产化学工业研究所江苏南京210042 江苏省生物质能源与材料重点实验室江苏南京210042

针对工业园区废水经上游企业处理后,可降解有机物含量低,活性污泥系统处理效果差、运行困难和深度处理成本高等问题,采用生物增效技术构建新的生物降解体系。实际运行结果表明,好氧出水COD较普通生化出水COD下降明显,平均出水COD从114 m... 详细信息

针对工业园区废水经上游企业处理后,可降解有机物含量低,活性污泥系统处理效果差、运行困难和深度处理成本高等问题,采用生物增效技术构建新的生物降解体系。实际运行结果表明,好氧出水COD较普通生化出水COD下降明显,平均出水COD从114 mg/L降至77.3 mg/L,平均COD去除率从24.40%升至50.90%;平均氨氮去除率从31.89%提高至76.07%;深度处理聚铁用量为1.35 kg/m^(3),出水COD基本稳定在30~40 mg/L,平均出水COD为37.4 mg/L、色度为4倍,运行成本较之前可节省1.45元/m^(3),两条处理线均采用增效技术后,按处理水量为3×10^(4) m^(3)/d计算,可节约成本1 522.50万元/a,实现了园区污水处理厂运行成本下降、出水水质提升的目标。

关键词：工业园区污水处理生物增效技术氨氮

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基于超单元法的大型邮轮总振动特性分析

武汉理工大学学报（交通科学与工程版） 2024年第4期48卷 675-680页

作者：竺欣悦朱玥甘进吴卫国武汉理工大学船海与能源动力工程学院武汉430063 武汉理工大学绿色智能江海直达船舶与邮轮游艇研究中心武汉430063

本文针对大型邮轮总振动数值预报方法展开研究,将超单元法应用于邮轮总振动分析中,对比分析超单元法相比传统直接计算方法在大型邮轮总振动分析中的优势,探讨超单元模型建立方式、设置数量以及残余结构选取对模态结果及计算效率的影响.... 详细信息

本文针对大型邮轮总振动数值预报方法展开研究,将超单元法应用于邮轮总振动分析中,对比分析超单元法相比传统直接计算方法在大型邮轮总振动分析中的优势,探讨超单元模型建立方式、设置数量以及残余结构选取对模态结果及计算效率的影响.结果表明:超单元法在邮轮这类大型结构总振动分析中具有更强的适用性,选用合适的超单元划分方式及数量可在保证计算精度的同时提高计算效率.

关键词：大型邮轮模态分析超单元法数值计算

维普期刊数据库博看期刊

Measurement of boiling heat transfer coefficient in liquid nitrogen bath by inverse heat conduction method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第5期10卷 691-696页

作者： Tao jin Jian-ping HONG Hao ZHENG Ke TANG Zhi-hua gan Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

Inverse heat conduction method (IHCM) is one of the most effective approaches to obtaining the boiling heat transfer coefficient from measured results. This paper focuses on its application in cryogenic boiling heat transfer. Experiments were conducted on the heat transfer of a stainless steel block in a liquid nitrogen bath, with the assumption of a 1D conduction condition to realize fast acquisition of the temperature of the test points inside the block. With the inverse-heat conduction theory and the explicit finite difference model, a solving program was developed to calculate the heat flux and the boiling heat transfer coefficient of a stainless steel block in liquid nitrogen bath based on the temperature acquisition data. Considering the oscillating data and some unsmooth transition points in the inverse-heat-conduction calculation result of the heat-transfer coefficient, a two-step data-fitting procedure was proposed to obtain the expression for the boiling heat transfer coefficients. The coefficient was then verified for accuracy by a comparison between the simulation results using this expression and the verifying experimental results of a stainless steel block. The maximum error with a revised segment fitting is around 6%, which verifies the feasibility of using IHCM to measure the boiling heat transfer coefficient in liquid nitrogen bath.

关键词： Inverse heat conduction method (IHCM) Liquid nitrogen bath Boiling heat transfer coefficient

Effect of a transverse plasma jet on a shock wave induced by a ramp

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Chinese Journal of Aeronautics 2017年第6期30卷 1854-1876页

作者： Hongyu WANG Jun LI Di jin Hui DAI Tian gan Yun WU Aeronautics and Astronautics Engineering College Air Force Engineering University Xi'an 710038 China

We conducted experiments in a wind tunnel with Mach number 2 to explore the evolution of a transverse plasma jet and its modification effect on a shock wave induced by a ramp with an angle of 24°. The transverse plasma jet was created by arc discharge in a small cylindrical cavity with a 2 mm diameter orifice. Three group tests with different actuator arrangements in the spanwise or streamwise direction upstream from the ramp were respectively studied to compare their disturbances to the shock wave. As shown by a time-resolved schlieren system, an unsteady motion of the shock wave by actuation was found： the shock wave was significantly modified by the plasma jet with an upstream motion and a reduced angle. Compared to spanwise actuation, a more intensive impact was obtained with two or three streamwise actuators working together. From shock wave structures, the control effect of the plasma jet on the shock motion based on a thermal effect, a potential cause of shock modification, was discussed. Furthermore, we performed a numerical simulation by using the Improved Delayed Detached Eddy Simulation（IDDES） method to simulate the evolution of the transverse plasma jet plume produced by two streamwise actuators. The results show that flow structures are similar to those identified in schlieren images. Two streamwise vortices were recognized, which indicates that the higher jet plume is the result of the overlap of two streamwise jets.

关键词： Flow control Improved delayed detachededdy simulation (IDDES)method Plasma synthetic jet Shock wave/boundary layerinteraction Time resolved schlierensystem

Effect of main inclusions on crack initiation in bearing steel in the very high cycle fatigue regime

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International Journal of Minerals,Metallurgy and Materials 2018年第6期25卷 623-629页

作者： Chao Gu Yan-ping Bao Peng gan Min Wang jin-shan He State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Steel Institute RWTH Aachen University

This work aims to investigate the effect of main inclusions on crack initiation in bearing steel in the very high cycle fatigue（VHCF） regime. The size and type of inclusions in the steel were quantitatively analyzed, and VHCF tests were performed. Some fatigue cracks were found to be initiated in the gaps between inclusions（Al2 O3, Mg O-Al2 O3） and the matrix, while other cracks originated from the interior of inclusions（Ti N, Mn S）. To explain the related mechanism, the tessellated stresses between inclusions and the matrix were calculated and compared with the yield stress of the matrix. Results revealed that the inclusions could be classified into two types under VHCF; of these two, only one type could be regarded as holes. Findings in this research provide a better understanding of how inclusions affect the high cycle fatigue properties of bearing steel.

关键词： very high cycle fatigue bearing steel inclusions tessellated slress crack initiation

Wnt/Glycogen Synthase Kinase 3β/β-catenin Signaling Activation Mediated Sevoflurane Preconditioning-induced Cardioprotection

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Chinese Medical Journal 2015年第17期128卷 2346-2353页

作者： jin-Dong Liu Qian deng Huan-Huan Tian Yun-Ting Pang gan-Lin deng Department of Anesthesiology The Affiliated Hospital of Xuzhou Medical College Jiangsu Province Key Laboratory of Anesthesiology Xuzhou Medical College Xuzhou Jiangsu 221004 China Jiangsu Province Key Laboratory of Anesthesiology Xuzhou Medical College Xuzhou Jiangsu 221004 China

Background： Sevoflurane preconditioning （SP） has been shown to invoke potent myocardial protection in animal studies and clinical trials. However, the mechanisms underlying SP are complex and not yet well understood. We investigated the hypothesis that the cardioprotection afforded by SP is mediated via the Writ/glycogen synthase kinase 3β（GSK3β）/β-catenin signaling pathway. Methods： Two models were established： A Langendorffperfused rat heart model and the H9C2 cell hypoxia/reoxygenation model. Both rats and H9C2 cells were randomly divided into 6 groups as follows： S group, ischemia-reperfusion （I/R） group, DMSO group, IWP group, SP group, and SP ＋ IWP group. Hemodynamic parameters, lactate dehydrogenase （LDH） activity in coronary effluent and cell culture supernatant, and the infarct size were measured to evaluate myocardial ischemia-reperfusion injuries. To determine the activity of Wnt/GSK3β/β-catenin signaling pathway, the expressions of Wnt3a, phospho-GSK3β, and β-catenin were measured by Western blotting. Results： SP improved cardiac function recovery, reduced infarct size （18 ±2% in the SP group compared with 35 ± 4% in the 1/R group; P 〈 0.05）, decreased LDH activity in coronary effluent, and culture supematant. IWP-2, an inhibitor of Wnt, abolished the cardioprotection by SR In addition, Western blotting analysis demonstrated that the expressions of Wnt3a, phospho-GSK3β, and β-catenin significantly （P 〈 0.05） increased in the I/R group, compared with the S group; and compared to I/R group, SP significantly （P 〈 0.05） increased Wnt3a, phospho-GSK3 β, and β-catenin expressions. Pretreatment with IWP-2 significantly （P 〈 0.05） abolished SP-induced Wnt/GSK3β/β-catenin signaling activation. Conclusions： The results showed for the first time that cardioprotection afforded by SP may be mediated partly via the Wnt/GSK3β/β-catenin signaling pathway.

关键词： Cardioprotection Ischemia-reperfusion Injury Preconditioning Sevoflurane Wnt/Glycogen Synthase Kinase3β/β-catenin Signaling

Facile ultrasonic-assisted synthesis of micro–nanosheet structure Bi_4Ti_3O_(12)/g-C_3N_4 composites with enhanced photocatalytic activity on organic pollutants

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Chinese Journal of Chemical Engineering 2018年第12期26卷 2628-2635页

作者： Huihui gan Futao Yi Huining Zhang Yongxing Qian Huixia jin Kefeng Zhang School of Civil Engineering and Architecture Ningbo Institute of Technology Zhejiang University College of Environmental Science and Engineering Guilin University of Technology

The Bi_4Ti_3O_(12)/g-C_3N_4 composites with microsheet and nanosheet structure were prepared through facile ultrasonic-assisted method. The SEM and TEM results suggested that the nanosheets g-C_3N_4 were stacked on the surface of regular Bi_4Ti_3O_(12) sheets. Comparing with pure Bi_4Ti_3O_(12) and g-C_3N_4, the Bi_4Ti_3O_(12)/g-C_3N_4 composites showed significant enhancement in photocatalytic efficiency for the degradation of RhB in solution. With the mass ratio of g-C_3N_4 increasing to 10 wt%, the Bi_4Ti_3O_(12)/g-C_3N_4-10% presented the best photocatalytic activity. Its photocatalysis reaction constant was approximately 2 times higher than the single component Bi_4Ti_3O_(12) or g-C_3N_4. Meanwhile, good stability and durability for the Bi_4Ti_3O_(12)/g-C_3N_4-10% were confirmed by the recycling experiment and FT-IR analysis. The possible mechanism for the improvements was the matched band positions and the effective separation of photo-excited electrons(e-) and holes(h+). Furthermore, based on the results of active species trapping, photo-generated holes(h+) and superoxide radical(·O2-) could be the main radicals in reaction.

关键词： Rhodamine B Photocatalyst Ultrasonic assisted synthesis Bi4Ti3O12 g-C3N4

基于多光谱技术对原儿茶酸抑制低密度脂蛋白氧化及其与牛血清白蛋白相互作用的研究

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光谱学与光谱分析 2024年第6期44卷 1762-1772页

作者：王晨雨陈成诚甘宇鑫张平平王峰星王月霞刘常金熊勇江慎华天津农学院食品科学与生物工程学院食品质量与安全系天津300392 九江学院药学与生命科学学院食品加工与安全九江市重点实验室江西九江332000 天津科技大学食品营养与安全国家重点实验室天津300457 六盘水师范学院贵州省高等学校猕猴桃资源开发与利用重点实验室贵州六盘水553004

植物多酚被称作人类健康的“第7类营养素”,在医药、食品和营养保健等多个领域受到广泛关注。红心猕猴桃果皮(RKP)中多酚含量丰富,是提取植物多酚的优良原料,但常被视为加工废料遭弃用。该研究拟通过脉冲超声(PU)辅助天然深共晶溶剂(NAD... 详细信息

植物多酚被称作人类健康的“第7类营养素”,在医药、食品和营养保健等多个领域受到广泛关注。红心猕猴桃果皮(RKP)中多酚含量丰富,是提取植物多酚的优良原料,但常被视为加工废料遭弃用。该研究拟通过脉冲超声(PU)辅助天然深共晶溶剂(NADES)提取RKP多酚,并通过荧光光谱和紫外-可见光谱探究RKP中重点多酚—原儿茶酸(PCA)抑制低密度脂蛋白(LDL)氧化功效及其与牛血清白蛋白(BSA)的相互作用机制。结果表明,NADES对RKP多酚的提取率显著高于常规溶剂(如水或乙醇)。在超声功率400 W、料液比1﹕40(g·mL^(-1))、温度70℃、提取20 min及含水率20%(ω/ω)条件下,所筛选的6种NADES溶剂中,氯化胆碱-乙二醇组合提取率最高(29.84 mg GAE/g DW)。光谱实验结果表明,PCA具有较强的DPPH自由基清除能力,清除率最高可达94.39%。PCA能够显著延长LDL氧化过程中共轭二烯(CD)生成的延滞时间及达到峰值时间,有效抑制脂质氧化过程中脂褐素及总荧光产物生成,减少LDL氧化过程中色氨酸(Trp)及赖氨酸(Lys)残基的氧化修饰,显示出对LDL氧化极强的抑制效果。多光谱法对PCA与BSA相互作用研究发现,两者之间存在相互作用,具有较强的亲和力,且只有一个结合位点,疏水作用力在相互作用过程中起主要作用;相互作用后酪氨酸(Tyr)周围微环境几乎不发生改变,而Trp周围微环境极性降低、疏水性增加;三维荧光光谱进一步证明二者之间存在相互作用,并由此引起蛋白质结构发生变化;综合荧光光谱和紫外-可见光谱的实验结果,PCA与BSA相互作用猝灭机理为静态猝灭。该研究为开发RKP及PCA提供参考。

关键词：多光谱技术红心猕猴桃果皮天然低共融溶剂原儿茶酸低密度脂蛋白