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Rare Metals 2011年第3期30卷 292-297页

作者： PENG Jiangqiang GUO Jian DING Shulong XU Qiao LI hang TAN Xuwei zhao Xian Faculty of Materials Optoelectronics and Physics Xiangtan University Xiangtan 411105 China

Mg-doped ZnO radial spherical structures with nanorods grown on both sides of the spherical shell were successfully prepared via chemical vapor deposition （CVD） of Zn and Mg powders in the absence of a catalyst. The structures associated with different growth temperatures （700, 800, and 850°C） were monitored by scanning electron microscopy （SEM）, and the result shows that the length of the nanorods increase progressively with the growth temperature increasing. X-ray diffraction （XRD） shows that the as-obtained samples can be indexed to high crystallinity with wurtzite structure. The growth of the nanostructures mainly depends on the formation of sphere-like Mg-doped Zn droplets before adding oxygen. Photoluminescence （PL） spectra that show a 39 meV blue shift indicates that the band gap becomes large, because Mg substitutes Zn in the lattice.

关键词： zinc oxide magnesium doping nanorods chemical vapor deposition photoluminescence spectroscopy

Development and experimental validation of a novel hybrid powertrain with dual planetary gear sets for transit bus applications

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Science China(Technological Sciences) 2015年第12期58卷 2085-2096页

作者： QIN KongJian WANG EnHua zhao hang SHI GuangKui WANG RenGuang KONG ZhiGuo WANG Wei State Key Laboratory of Automotive Safety and Energy Tsinghua University China Automotive Technology and Research Center

Given that energy conservation and environmental protection are two important goals for the automotive industry, the application of a hybrid electric powertrain can improve vehicle energy efficiency while decreasing fuel consumption and engine emissions. Planetary gear-based power-split hybrid powertrains have become widely used in passenger vehicles, but remain rarely employed on transit buses. This study proposes a novel hybrid powertrain based on two planetary gear sets(CHS) and presents its operating principles along with development of a control strategy for the powertrain. The CHS hybrid powertrain operates in electric mode when the driving power demand is low, and changes to a hybrid electric mode according to the power-split principle of the planetary gear set. To validate the feasibility of the designed CHS hybrid powertrain, a prototype transit bus equipped with the designed hybrid powertrain system was built, and the operating characteristics of the system were analyzed through a performance test conducted on a chassis dynamometer. Compared with a conventional powertrain, the CHS hybrid powertrain can reduce fuel consumption by 39%. Thus, the CHS hybrid powertrain is a good solution for heavy-duty applications such as hybrid transit buses because of its simple structure and excellent fuel efficiency.

关键词： dual planetary gear set hybrid powertrain experimental validation transit bus performance analysis

高增益耦合电感组合Boost-Sepic变换器

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电力电子技术 2024年第6期58卷 61-63,71页

作者：房绪鹏郭红震王腾翡赵航山东科技大学电气与自动化工程学院山东青岛266590

传统的DC/DC变换器由于其寄生损耗,在高占空比下提供的实际增益有限,对此,此处提出一种高增益耦合电感组合Boost-Sepic变换器。该变换器将耦合电感与开关电容相结合,构成耦合电感倍压单元实现变换器的高电压增益,同时开关电容中的二极... 详细信息

传统的DC/DC变换器由于其寄生损耗,在高占空比下提供的实际增益有限,对此,此处提出一种高增益耦合电感组合Boost-Sepic变换器。该变换器将耦合电感与开关电容相结合,构成耦合电感倍压单元实现变换器的高电压增益,同时开关电容中的二极管和电容作为无源电压箝位支路,回收耦合电感中漏感储存的能量,而且拓扑组合结构还保留了开关管的无源电压箝位支路,保证了开关管的低电压应力。此处详细分析了该新型Boost-Sepic变换器,包括工作模态、电压增益、开关器件电压应力及器件参数的选择,并与其他高增益变换器进行对比。最后,通过200 W实验样机验证了该变换器的可行性和优点。

关键词：变换器高增益耦合电感箝位支路

K-19 mRNA RT-PCR in detecting micrometastasis in regional lymph nodes of gastric cancer

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World Journal of Gastroenterology 2006年第32期12卷 5219-5222页

作者： Jian Suo Quan Wang Hong-Juan Jin Hong Li hang zhao Department of General Surgery First Hospital Changchun 130021 Jilin Province China

AIM： To investigate the value and prospect of RT-PCR in detecting micrometastasis in regional lymph nodes of gastric cancer. METHODS： Histopathology was used and K19 mRNA expression was detected by RT-PCR in tumor tissues and lymph nodes from gastric cancer patients undergoing radical resection of gastric carcinoma. RESULTS： K19 mRNA was expressed in all tumor specimens of 30 cases; of the 126 lymph nodes, 26 were histopathologically positive （20.6%）, and 42 positive （33.3%） by RT-PCR. Amplification fragments of 460 and 540 bp were shown in all the tumor tissues and metastatic lymph nodes after K19 and β-actin RT-PCR, while only a 540 bp fragment appeared in the lymph nodes of non-tumor patients. CONCLUSION： K19 mRNA RT-PCR is sensitive and specific in testing micrometastasis in regional lymph nodes of gastric cancer, and it is superior to routine histopathology.

关键词： K-19 mRNA RT-PCR Micrometastasis Gastric cancer

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先导式低压输灰技术节能分析

今日自动化 2024年第6期 53-55页

作者：王铮赵航解晨晨成亮郭顺强河北华电石家庄鹿华热电有限公司河北石家庄050000

河北华电石家庄鹿华热电有限公司输灰技术采用正压浓相双套管气力输灰技术,随着运行时间的增加,出现耗气量增加、输灰出力不足、管道和设备磨损严重等问题。文章对原输灰系统应用先导低压输送技术进行改造,并对其进行性能试验,从耗气量... 详细信息

河北华电石家庄鹿华热电有限公司输灰技术采用正压浓相双套管气力输灰技术,随着运行时间的增加,出现耗气量增加、输灰出力不足、管道和设备磨损严重等问题。文章对原输灰系统应用先导低压输送技术进行改造,并对其进行性能试验,从耗气量、输送压力、输送速度、出力及输送频次等方面与原输灰系统进行对比。

关键词：先导低压输送技术节气率输送频次

Emerging role of autophagy in colorectal cancer:Progress and prospects for clinical intervention

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World Journal of Gastrointestinal Oncology 2023年第6期15卷 979-987页

作者： Tian-Fei Ma Yue-Ren Fan Yi-hang zhao Bin Liu Department of Breast Internal MedicineⅡ Cancer Hospital of China Medical UniversityLiaoning Cancer Hospital&InstituteShenyang 110042Liaoning ProvinceChina

Autophagy is a physiological mechanism in which cells degrade themselves and quickly recover the degraded cell *** studies have shown that autophagy plays an important role in the occurrence,development,treatment,and prognosis of colorectal *** the early stages of colorectal cancer,autophagy can inhibit the production and development of tumors through multiple mechanisms such as maintaining DNA stability,inducing tumor death,and enhancing immune ***,as colorectal cancer progresses,autophagy may mediate tumor resistance,enhance tumor metabolism,and other pathways to promote tumor ***,intervening in autophagy at the appropriate time has broad clinical application *** article summarizes the recent research progress of autophagy and colorectal cancer and is expected to provide new theoretical basis and reference for clinical treatment of colorectal cancer.

关键词： Autophagy Self-degradation Colorectal cancer Phosphatidylinositol-3-phosphate Immune cells

Optimization of microwave pretreatment of lignocellulosic waste for enhancing methane production： Hyacinth as an example

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Frontiers of Environmental Science & Engineering 2017年第6期11卷 161-169页

作者： Bai-hang zhao Jie Chen Han-Qing Yu Zhen-Hu Hu Zheng-Bo Yue Jun Li Department of Municipal Engineering Beijing University of Technology Beijing 100124 China Department of Chemistry University of Science & Technology of China Hefei 230026 China School of Civil Engineering Hefei University of Technology Hefei 230092 China

The effect of microwave pretreatment on the anaerobic degradation of hyacinth was investigated using response surface methodology （RSM）. The components oflignin and the other constituents of hyacinth were altered by microwave pretreatment. Comparison of the near-infrared spectra of hyacinth pretreated by microwave irradiation and water-heating pretreatment revealed that no new compounds were generated during hyacinth pretreatment by microwave irradiation. Atomic force microscopy observations indicated that the physical structures of hyacinth were disrupted by microwave pretreatment. The yield of methane per gram of the microwave-irradiated substrate increased by 38.3% as compared to that of the substrate pretreated via water-heating. A maximum methane yield of 221 mL·g-sub^-1 was obtained under the optimum pretreatment conditions （substrate concentration （pSC） = 20.1 g·L^-1 and pretreatment time （PT） = 14.6 min） using RSM analysis. A maximum methane production rate of 0.76 mL·h^-1· g-sub^-1 was obtained by applying PSC = 9.5 g·L^-1 and PT= 11 min. Interactive item coefficient analysis showed that methane production was dependent on the PSC and PT, separately, whereas the interactive effect of the PSC and PT on methane production was not significant. The same trend was also observed for the methane production rate.

关键词： Microwave pretreatment Response surface methodology Methane production Hyacinth Anaerobic digestion

鄂尔多斯盆地南部山西组致密储层的分形特征及其影响因素分析

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非常规油气 2024年第2期11卷 37-45页

作者：赵航罗腾跃贺沛孙建峰李涛陕西延长石油(集团)有限责任公司研究院西安710065

为了对鄂尔多斯盆地南部致密储层微观物性进行研究,以研究区山西组为例,利用压汞资料、铸体薄片和岩心资料,引入分形理论,定量分析了研究区致密储层微观物性和孔喉特征。结果表明:1)研究区山西组分形维数主要分布在2.15~2.81,表明储层... 详细信息

为了对鄂尔多斯盆地南部致密储层微观物性进行研究,以研究区山西组为例,利用压汞资料、铸体薄片和岩心资料,引入分形理论,定量分析了研究区致密储层微观物性和孔喉特征。结果表明:1)研究区山西组分形维数主要分布在2.15~2.81,表明储层微观孔隙的非均质性较强;2)研究区分形维数与储集岩多种物性参数存在良好的相关性。分形维数可以定量表征储层微观孔隙特征,即分形维数越小,储层物性及非均质性越好,渗流能力越强;3)分形维数可以定量表征储层微观物性特征,可以应用分形维数对储集层进行分类评价;4)影响致密储层物性的主要因素是沉积相和岩石的矿物成分。以上结果,为研究区下一步的稳产开发提供理论依据。

关键词：鄂尔多斯盆地山西组致密储层分形特征

Microstructure and high-temperature wear properties of in situ TiC composite coatings by plasma transferred arc surface alloying on gray cast iron

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1273-1282页

作者： hang zhao Jian-jun Li Zhi-zhen Zheng Ai-hua Wang Qi-wen Huang Da-wen Zeng State Key Laboratory of Material Processing and Die & Mould Technology Huazhong University of Science & Technology

In this work, an in situ synthesized TiC-reinforced metal matrix composite （MMC） coating of approximately 350-400μm thickness was fabricated on a gray cast iron （GCI） substrate by plasma transferred arc （PTA） surface alloying of Ti-Fe alloy powder. Microhard- ness tests showed that the surface hardness increased approximately four-fold after the alloying treatment. The microstructure of the MMC coating was mainly composed of residual austenite, acicular martensite, and eutectic ledeburite. Scanning electron microscopy （SEM） and X-ray diffraction analyzes revealed that the in situ TiC particles, which were formed by direct reaction of Ti with carbon originally contained in the GCI, was uniformly distributed at the boundary of residual anstenite in the alloying zone. Pin-on-disc high-temperature wear tests were performed on samples both with and without the MMC coating at room temperature and at elevated temperatures （473 K and 623 K）, and the wear behavior and mechanism were investigated. The results showed that, after the PTA alloying treatment, the wear resistance of the sam- ples improved significantly. On the basis of our analysis of the composite coatings by optical microscopy, SEM with energy-dispersive X-ray spectroscopy, and microhardness measurements, we attributed this improvement of wear resistance to the transformation of the microstruc- ture and to the presence of TiC particles.

关键词： gray cast iron composite coatings particle-reinforced composites titanium carbide surface alloying microstructure wear