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A fast registration algorithm of rock point cloud based on spherical projection and feature extraction

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Frontiers of Computer Science 2019年第1期13卷 170-182页

作者： Yaru xian jun XIAO Ying WANG School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China

Point cloud registration is an essential step in the process of 3D *** this paper,a fast registration algorithm of rock mass point cloud is proposed based on the improved iterative closest point (ICP)*** our proposed algorithm,the point cloud data of single station scanner is transformed into digital images by spherical polar coordinates,then image features are extracted and edge points are removed,the features used in this algorithm is scale-invariant feature transform (SIFT).By analyzing the corresponding relationship between digital images and 3D points,the 3D feature points are extracted,from which we can search for the two-way correspondence as candidates. After the false matches are eliminated by the exhaustive search method based on random sampling,the transformation is computed via the Levenberg-Marquardt-Iterative Closest Point (LM-ICP)*** on real data of rock mass show that the proposed algorithm has the similar accuracy and better registration efficiency compared with the ICP algorithm and other algorithms.

关键词： rock point cloud registration LM-ICP spherical projection feature extraction

A facile synthesis of the spiroindoline-based growth hormone secretagogue,MK-677

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Chinese Chemical Letters 2012年第6期23卷 661-664页

作者： xian Liang qi Er Qun Yang jun Tao Zhang Tao Wang Xiao Ping Cao State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 China

A facile and improved route for the synthesis of the orally active spiroindoline-based growth hormone secretagogue, MK-677 was described. The key step adopted the Fischer indole/reduction strategy. The preparation of the key intermediates N-protected piperidine carboxaldehyde 5 and the N-Boc-O-benzyl-D-serine （2） are also optimized.

关键词： MK-677 Synthesis Improved route Fischer indole/reduction

Accuracy of early detection of colorectal tumours by stool methylation markers:A meta-analysis

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World Journal of Gastroenterology 2014年第38期20卷 14040-14050页

作者： Hu Zhang Jian qi Ya-qiong Wu Ping Zhang jun Jiang qi-xian Wang You-qing Zhu Department of Gastroenterology and Clinical Centre of Intestinal and Colorectal Diseases of Hubei Province Zhongnan Hospital of Wuhan University Department of Gastroenterology Hubei Provincial Corps HospitalChinese People’s Armed Police Force Department of Dermatology Yijishan Hospital of Wannan Medical College

AIM: To evaluate the accuracy of methylation of genes in stool samples for diagnosing colorectal tumours.

关键词： Colorectal carcinoma Colorectal adenoma Stool Methylation Meta-analysis

Test research on sticking mechanism during hot rolling of SUS 430 ferritic stainless steel

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 573-578页

作者： jun-xian Liu Yong-jun Zhang Jing-tao Han School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The sticking phenomenon during hot rolling of SUS 430 ferritic stainless steel was investigated by means of a two-disc type high-temperature wear tester. The test results indicate that sticking particles on the surfaces of high chromium steel （HiCr） and high-speed steel （HSS） rolls undergo nucleation, growth, and saturation stages. Grooves on the roll surface generated by grinding provide nucleation sites for sticking particles. The number of sticking particles on the HiCr roll surface is greater than that on the HSS roll surface. The average surface roughnesses （Ra） of HiCr and HSS rolls change from 0.502 and 0.493 μm at the initial stage to 0.837 and 0.530 μm at the saturation stage, respectively. The test further proves that the sticking behavior is strongly dependent on roll materials, and the HSS roll is more benefi- cial to prevent particles sticking compared with the HiCr roll under the same hot-rolling conditions.

关键词： ferritic steel stainless steel hot rolling sticking rolls

Synthesis and Characterization of Thiacalix[4] arene Derivatives with Polymerisable Groups

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Chemical Research in Chinese Universities 2007年第2期23卷 241-244页

作者： GU Jin-ying HU Xiao-jun SHI xian-fa LI Yan-jun qi Yong-lu JI Liang-nian Department of Chemistry Tongji University Shanghai 200092 P. R. China School of Chemistry and Chemical Engineering Zhongshan University Guangzhou 510275. P. R. China

Introduction Calixarenes are versatile host molecules for molecular recognition and supramolecular assembly because its functional groups can be readily introduced into the phenolic OH or the para position to realize a wide variety of functions calixarenes-based polymers tion as these polymers can During the past decade, received increasing attenbe used to synthesize the materials that are suitable for the preparation of chemical sensor devices such as ion-selective electrodes or transport membranes.

关键词： Synthesis Characterization Thiacalix arene derivative Polymerisable group

New influence factor inducing difficulty in selective flotation separation of Cu–Zn mixed sulfide minerals

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International Journal of Minerals,Metallurgy and Materials 2015年第2期22卷 111-115页

作者： Jiu-shuai Deng Ying-bo Mao Shu-ming Wen Jian Liu Yong-jun xian qi-cheng Feng State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource Engineering Kunming University of Science and Technology

Selective flotation separation of Cu-Zn mixed sulfides has been proven to be difficult. Thus far, researchers have found no satis- factory way to separate Cu-Zn mixed sulfides by selective flotation, mainly because of the complex surface and interface interaction mecha- nisms in the flotation solution. Undesired activation occurs between copper ions and the sphalerite surfaces. In addition to recycled water and mineral dissolution, ancient fluids in the minerals are observed to be a new source of metal ions. In this study, significant amounts of ancient fluids were found to exist in Cu-Zn sulfide and gangue minerals, mostly as gas-liquid fluid inclusions. The concentration of copper ions re- leased from the ancient fluids reached 1.02 × 10-6 tool/L, whereas, in the cases of sphalerite and quartz, this concentration was 0.62 ×10-6 mol/L and 0.44 × 10-6 mol/L, respectively. As a result, the ancient fluid is a significant source of copper ions compared to mineral dissolution under the same experimental conditions, which promotes the unwanted activation of sphalerite. Therefore, the ancient fluid is considered to be a new factor that affects the selective flotation separation of Cu-Zn mixed sulfide ores.

关键词： sulfide minerals flotation separation fluid inclusions

Discovering genes responsible for silk synthesis in Bombyx moriby piggyBac-based random insertional mutagenesis

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Insect Science 2019年第5期26卷 821-830页

作者： Xing-Bao Feng Zi-Wen Zheng xian Zhang jun Gu qi-Li Feng Li-Hua Huang Guangzhou Key Laboratory of Insect Development Regulation and Applied Research Institute of Insect Science and TechnologySchool of Life SciencesSouth China Normal UniversityGuangzhouChina

Silkworm mutants are valuable resources for both transgenic breeding and gene discovery. PiggyBac-based random insertional mutagenesis has been widely used in gene functional studies. In order to discover genes involved in silk synthesis, a piggyBac-based random insertional library was constructed using Bombyx mori, and the mutants with abnormal cocoon were particularly screened. By this means, a “thin cocoon” mutant was identified. This mutant revealed thinner cocoon shell and shorter posterior silk gland (PSG) compared with the wild type. The messenger RNA (mRNA) levels of all the three fibroin genes, including Fib-H, Fib-L and P25, were significantly down-regulated in the PSG of mutants. Four piggyBac insertion sites were identified in Aquaporin (AQP), Longitudinals lacking protein-like {Lola), Glutamyl aminopeptidase-like (GluAP) and Loc101744460. The mRNA levels of all the four genes were significantly altered in the silk gland of mutants. In particular, the mRNA amount of AQP, a gene responsible for the regulation of osmotic pressure, decreased dramatically immediately prior to the spinning stage in the anterior silk gland of mutants. The identification of the genes disrupted in the “thin cocoon” mutant in this study provided useful information for understanding silk production and transgenic breeding of silkworms in the future.

关键词： aquaporin Bombyx mori development mutant piggyBac silk gland

Alloying Design for High Wear-Resistant Cast Hot-Forging Die Steels

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Journal of Iron and Steel Research International 2008年第4期15卷 67-72页

作者： CUI xiang-hong SHAN jun YANG Zi-run WEI Min-xian WANG Shu-qi DONG Chuang School of Materials Science and Engineering Jiangsu University Zhenjiang 212013 Jiangsu China Harbin Zhuoyue Information Technology Advance Limited Company Harbin 150001 Heilongjiang China State Key Laboratory of Materials Modification by Laser Ion and Electron Beams Dalian University of Technology Dalian 116024 Liaoning China

The alloying design of cast hot-forging die steels was analyzed. The relationship of the life of cast hot-forging dies with the failure patterns was studied. The thermal wear resistance was believed to be the key property for the alloying design of cast hot-forging die steels. The alloying design parameters were selected and optimized for the cast hot-forging die steel with high wear resistance. The wear resistance of the optimized cast die steel was evaluated in comparison with commercial H13 steels and 3Cr2WSV steel. In the new cast hot-forging die steel, VC is predominant carbide with Cr and Mo as the main solution elements in α-Fe. It is found that the cast die steel has significantly lower wear rate than normal H13 steel and 3Cr2W8V steel, almost the same as that of high purity H13 steel. The high wear resistance of the new cast hot-forging die steel can be attributed to its reasonable alloying design and nonsensibility to the detrimental function of S and P.

关键词： hot-forging die cast steel wear resistance alloying design

^(174)Hf and^(174)Yb by the Projected Shell Model with Improved 4-quasiparticle basis

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Chinese Physics Letters 2011年第4期28卷 71-74页

作者： CHEN Fang-qi ZHOU xian-Rong Department of Physics and Institute of Theoretical Physics and Astrophysics Xiamen UniversityXiamen 361005

The rare-earth nuclei^(174)Hf and^(174)are studied in the framework of the projected shell *** calculations are carried out with an improved version of code which contains all types of four-quasiparticle basis in the configuration *** the yrast band and the multi-quasiparticle excited bands can be well *** with the experimental data,our calculations improve the previous resulst,especially for high spin *** improvement suggests that the newly added configurations are ***^(174)Yb,a new possible configuration is suggested for the observed K^(л)=14^(+)band,and the decay of the K^(л)=6^(+)isomeric state to the yrast band is discussed.

关键词： space quasi particle