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林地承包合同不宜轻易解除

人民司法 2024年第5期 49-51页

作者：高俊华海南省高级人民法院

【裁判要旨】承包人改变承包地用途,只要未改变农用地性质,不构成违约。承包人将土地转包是否构成违约视转包后的用途而定。因林业生产经营周期和承包期比较长,收益慢,即使承包人违约,也不宜轻易解除,可以令其承担其他违约责任。

关键词：林业生产土地转包裁判要旨违约责任承包期农用地承包地承包人

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基于地层变异性的大直径盾构隧道鲁棒性设计

湖南大学学报（自然科学版） 2024年第9期51卷 46-54页

作者：张冬梅李海云黄忠凯谭飞朱美恒杨光高俊华同济大学地下建筑与工程系上海200092 同济大学岩土及地下工程教育部重点实验室上海200092 中国地质大学(武汉)工程学院湖北武汉430074 中交隧道工程局有限公司上海机场联络线项目部江苏南京211106

大直径盾构隧道面临着复杂地层带来的挑战,传统的设计方法往往选择钻孔揭示的最不利地层断面或者采用平均化的地层,无法准确反映掘进面临的真实地层情况.因此,利用现有钻孔勘察信息建立耦合马尔可夫链模型,确定盾构掘进过程中最可能穿... 详细信息

大直径盾构隧道面临着复杂地层带来的挑战,传统的设计方法往往选择钻孔揭示的最不利地层断面或者采用平均化的地层,无法准确反映掘进面临的真实地层情况.因此,利用现有钻孔勘察信息建立耦合马尔可夫链模型,确定盾构掘进过程中最可能穿越的典型地层断面.采用不同设计参数展开数值模拟,以盾构隧道收敛变形相关指标的标准差作为鲁棒性指标,提出了一种基于地层变异性的大直径盾构隧道鲁棒性设计方法.研究结果表明,耦合马尔可夫链模型的最典型断面为盾构隧道提供了更准确的地层条件,使得鲁棒性设计更具适用性.最后,对现阶段常用的地层设计方法进行了优化,确保掘进过程中地层选择更接近实际情况,在有效降低隧道建设成本的同时,使得隧道具备更好的鲁棒性.

关键词：地层变异性岩土参数变异性耦合马尔可夫链模型鲁棒性

Influence of an External Magnetic Field on the Growth of Nanocrystalline Silicon Films Grown by MF Magnetron Sputtering

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Journal of Materials Science & Technology 2012年第11期28卷 992-998页

作者： junhua gao Lin Zhang Jinquan Xiao Jun Gong Chao Sun Lishi Wen State Key Laboratory for Corrosion and Protection Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The effects of an external magnetic field originating from two solenoid coils on the magnetic field configuration, plasma state of a dual unbalanced magnetron sputter system and the structure of nanocrystalline Si films were examined. Numerical simulations of the magnetic field configuration showed that increasing the coil current significantly changed the magnetic field distribution between the substrate and targets. The saturated ion current density Ji in the substrate position measured by using a circular flat probe increased from 0.18 to 0.55 mA/cm2 with the coil current ranging from 0 to 6 A. X-ray diffraction and Raman results revealed that increasing the ion density near the substrate would benefit crystallization of films and the preferential growth along [lI1] orientation. From analysis of the surface morphology and the microstructure of Si films grown under different plasma conditions, it is found that with increasing the Ji, the surface of the film was smoothed and the alteration in the surface roughness was mainly correlated to the localized surface diffusion of the deposited species and the crystallization behavior of the films.

关键词： Nanocrystalline silicon Thin film Solenoid coil MF magnetron sputtering

Preparation and Characterization of High Infrared Emissivity Mn-doped NCO Spinel Composites

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Journal of Wuhan University of Technology(Materials Science) 2017年第6期32卷 1265-1270页

作者：邹隽 DONG Shurong gao junhua WANG Hongfu 程旭东 State Key Laboratory of A-dvanced Technology for Materials Synthesis and Processing WuhanUniversity of Technology Wuhan 430070China College of Mechanical and Power Engineering China Three Gorges University Yichang 443002 China School of Mechanical Engineering North University of China Taiyuan 030051 China

NiCr2O4（NCO）spinel composites with different Mn/Ni atomic ratios（Mn/Ni=0.05,0.10,0.15,and 0.20）were synthesized via solid state reaction *** compositions and microstructure of samples were characterized by X-ray diffraction（XRD）and X-ray photoelectron spectroscopy（XPS）.The TG-DSC curves showed that the appropriate baking temperature for Mn-doped NCO spinel preparation was approximately 1 320℃.X-ray diffraction patterns exhibited the formation of NCO spinel with Fd-3m space *** state of the Mn ions was determined from 2p and 3s X-ray photoelectron *** ions were mostly in divalent and trivalent states,and the ratio of Mn^2＋/Mn^3＋was *** transform infrared spectroscopy（FTIR）was used to analyze the spectral emissivity of Mn doped NCO *** was revealed that the infrared emissivity of Mn-doped NCO spinel in 1.8-5μm could be significantly enhanced with increasing content of Mn^2＋,reaching as high as ***-doped NCO spinel showed excellent radiation performance and good prospect in high emissivity applications in the temperature range of 800-1 200℃.

关键词： NCO infrared emissivity Mn doped spinel XPS

大直径盾构始发端头加固区域隧道变形差异特征实测研究

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城市轨道交通研究 2024年第7期27卷 113-119,126页

作者：杨光高俊华甘彬霖黄忠凯张吾渝张冬梅中交隧道工程局有限公司上海机场联络线项目部南京211106 同济大学上海自主智能无人系统科学中心上海200092 同济大学土木工程学院上海200092 青海大学土木水利学院西宁810016

[目的]为保证盾构顺利始发,通常对始发工作井周围区域进行局部地层加固,导致加固区域两侧隧道变形存在差异,影响隧道结构安全,但目前变形差异特征及其规律尚不明确,因此有必要对大直径盾构始发端头加固区域隧道变形的差异特征进行实测... 详细信息

[目的]为保证盾构顺利始发,通常对始发工作井周围区域进行局部地层加固,导致加固区域两侧隧道变形存在差异,影响隧道结构安全,但目前变形差异特征及其规律尚不明确,因此有必要对大直径盾构始发端头加固区域隧道变形的差异特征进行实测研究。[方法]以上海市域铁路机场联络线大直径盾构隧道工程为例,基于现场实测数据,分析了始发工作井加固区域盾构掘进施工地面竖向变形、隧道竖向变形、隧道横向收敛的差异特征,分析了地层局部加固对软土地层大直径盾构隧道掘进差异变形的影响规律。[结果及结论]地层局部加固导致盾构隧道变形响应差异显著;地面竖向变形发展由非加固区的扰动沉降、卸荷隆起、固结沉降和相对稳定4个阶段,转变为加固区的扰动沉降、卸荷隆起和相对稳定3个阶段;对于隧道竖向变形,非加固区一侧以波动上浮为主,加固区以沉降为主,导致临界区域差异沉降达到0.022%L s(L s为隧道轴线两个监测点间距),超过管片结构差异沉降预警值;对于隧道横向收敛,加固区隧道结构呈竖鸭蛋变形特征,非加固区呈横鸭蛋变形特征;施工中,应重点防范临界区域管片结构差异沉降和差异收敛造成的环缝螺栓剪切破坏和螺栓孔混凝土损伤。

关键词：盾构隧道端头加固区域隧道变形差异现场监测

Milling Research and Tool Selection Design of SiC14Cu4Mg0.5Si based on Aluminium Matrix 2A14

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Journal of Wuhan University of Technology(Materials Science) 2016年第6期31卷 1377-1380页

作者：王兴文祝锡晶 gao junhua ZHENG Zhizhen WANG Huajun School of Mechanical and Power Engineering North University of China Taiyuan 030051 China School of Materials Science and Engineering Wuhan University of Technology Wuhan 430070 China

The selection of milling tools for Si C14Cu4Mg0.5Si based on Aluminium matrix 2A14 was analyzed, and the factors that affect the efficiency of the milling were discussed. The Si C14Cu4Mg0.5Si was designed for use on the moon landing vehicle or missile wings, but the hardness of aluminium-silicon carbide composite material was very high, much higher than the general hardness of cemented carbide, which will bring many difficulties in the aluminium-silicon carbide composite material processing. The chemical compositions of Si C14Cu4Mg0.5Si were analyzed. A new selected indexable cutter was designed to mill Si C14Cu4Mg0.5Si. The structure design of milling cutter was different from the conventional milling cutter, breaking the previous limitations to a certain extent, pioneering the idea. The tool material wear was detected by experiments. The mechanical and physical properties of Si C14Cu4Mg0.5Si were also tested. Si C14Cu4Mg0.5Si exhibited different surface quality characteristics under different milling tools.

关键词： aluminium matrix silicon carbide milling surface quality Si C14Cu4Mg0 5Si milling tool

Synthesis and characterization of BZSM-5 and its catalytic performance in the methanol to hydrocarbons reaction

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Chinese Journal of Chemical Engineering 2021年第7期34卷 196-203页

作者： junhua gao Keming Ji Hao Zhou Jiayao Xun Zenghou Liu Kan Zhang Ping Liu State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China

Five kinds of BZSM-5 molecular sieve with different Si/B ratio and a SiZSM-5 molecular sieve were prepared by hydrothermal synthesis method followed by acid exchange and *** samples were characterized by XRD,SEM,FT-IR,ICP,low temperature N_(2) physical adsorption and desorption,NH3-TPD and *** catalytic performance in the reaction of methanol to hydrocarbons was evaluated in the fixed bed *** with SiZSM-5,the amount and strength of Bronsted(B)acid were enhanced by introducing skeleton boron and the activity of the catalyst was greatly *** characterization and evaluation results indicated that the BZSM-5 catalyst synthesized from the gel of SiO_(2)/B2 O320 with Si/B ratio 74.48 had modest acidity strength,acid amount of 0.18 mmol NH3·g^(-1) and large mesopore volume of 0.23 cm3·g^(-1).The B acid ratio was higher and the acid strength of BZSM-5 was weaker than that of AIZSM-5,which could inhibit the deep coke formation and increase the activity stability.B-2 had the best lifetime which could reach 672 h under the same evaluation reaction conditions,due to the best matching of moderate acidity and good diffusion properties.

关键词： ZSM-5 Catalysis Methanol Hydrocarbons

The study of methanol aromatization on transition metal modified ZSM-5 catalyst

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Chinese Journal of Chemical Engineering 2018年第9期26卷 1949-1953页

作者： Keming Ji Jiayao Xun Ping Liu Qingwen Song junhua gao Kan Zhang Jingyuan Li State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences

In this article, transition metals of Cu, La and Zn were used as adjuvant to prepare modified HZSM-5 by impregnation method. The catalysts were characterized by XRD, BET, NH_3-TPD and Py-IR to reveal the microstructure and acid property. The catalysis performances of methanol aromatization of catalysts were investigated in a fixed-bed reactor. The results show that the strength and distribution of acid center of these catalysts are significantly influenced by the species of transition metal. There are more mediate strong Lewis acid center in Zn modified HZSM-5 catalyst and therefore exhibits higher selectivity to aromatic, benzene, toluene and xylenes in the MTA reaction..

关键词： Aromatization ZSM-5 Metal modified

Effects of nanoparticle structural features on the light-matter interactions in nanocermet layers and cermet-based solar absorbers

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Journal of Materiomics 2021年第5期7卷 1103-1111页

作者： Xiaoyu Wang Houjin He junhua gao Haibo Hu Shiwei Tang Xiaoyun Li Xiuhong Li Hongtao Cao Ningbo Institute of Materials Technology&Engineering Chinese Academy of SciencesNingbo 315201China School of Physical Science and Technology Ningbo UniversityNingbo 315211China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China

Metallic nanoparticle(NP)/ceramic composite cermets present desirable broadband absorption of the solar spectrum and thus are the preferred material scheme for constructing cermet-based solar ***,the effects of fine nanoparticle structural features on the light-matter interactions in nanocermet layers and corresponding cermet-based solar absorbers are still not well clear until ***,we report a systematical investigation on the effects of W(tungsten)nanoparticle sizes,its concentrations and configurations in an alumina matrix on the optical responses of WeAl_(2)O_(3) nanocermet layers and a solar absorber with double-cermet *** is found that to possess admirable light absorption features at high temperatures,it is better to maintain the fine particle size of less than 10 nm,isolated states and suitable separations between them for WeAl_(2)O_(3) ***,the dominated intrinsic absorption of W NPs,their plasmonic excitation and coupling effects among each other all contribute significantly to the broadband optical performance of the cermet layers and the whole *** importantly,this study demonstrates a valuable criterion for maintaining optical performances of nanocermet layers and cermet-based solar absorbers under heating and thus their thermal robustness.

关键词： Nanocermet Solar absorbers Tungsten Plasmonic interaction Thermal stability