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Acta Oceanologica Sinica 2000年第2期19卷 37-44页

作者： chen Feizhou1 Huang Yipu2 chen min2 (1. College of Fishery Science, Shanghai Fisheries University, Shanghai 200090, China 2. Department of Oceanography, Xiamen University, Xiamen 361005, China) College of Fishery Science Shanghai Fisheries University Shanghai 200090 China

The spatial and temporal distributions of new production vary largely in different sea areas. To understand the level of new production in the sea area studied better, an estimate of new production must be obtained in large spatial and temporal scales. The ~234Th/ ~238U disequilibrium is an effective method for the study of new production. Two sampling strategies, vertically integrated sampling ap proach based on trapezoidal integration principle and discrete layer sampling approach, were compared in the studies of the xiamen Bay and the northern South China Sea. The scavenging fluxes and removal fluxes of ~234Th and the residence times for dissolved and particulate ~234Th were calculated. The coinci dent results from two Sampling approach suggest that vertically integrated sampling approach is not only effective and reliable, but also significantly reduces the number and volume of samples. It allows us to study new production by ba ^(234)Th - ^(238)U disequilibria in large spatial scale.

关键词： New production vertically integrated Sampling approach, ^(234)Th - ^(238)U disequilibria Xia men Bay northern South China Sea

Structure,Electrical Conducting and Thermal Expansion Properties of Ln_(0.6)Sr_(0.4)Co_(0.8)Fe_(0.2)O_3(Ln=La,Pr,Nd,Sm)Ceramics

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Journal of Wuhan University of Technology(Materials Science) 2008年第3期23卷 386-390页

作者：徐庆 School of Materials Science and Engineering Wuhan University of Technology

Ln0.6Sr0.4Co0.2Fe0.2O3 （Ln=La, Pr, Nd, Sm） perovskite-type complex oxides were synthesized using a glycine-nitrate process, and the structure, electrical conducting and thermal expansion properties of the resulting ceramics were examined with regard to the nature of the lanthanide cations. The results indicated that the La, Pr and Nd specimens had a rhombohedral symmetry, while an orthorhombic structure was determined for the Sm specimen. The pseudo-cubic lattice constant decreased with smaller lanthanide cations. It was found that the electrical conducting properties declined with decreasing lanthanide cation size. Fortunately, all the compositions remained rather high electrical conductivities exceeding 650 Ω ^-1m·cm^-1 in the intermediate temperature range （600-800 ℃）. An appreciable thermal expansion increase at high temperatures was detected for all the compositions. Decreasing the size of the lanthanide cations resulted in an increase of thermal expansion. With respect to the high electrical conductivities, the Ln0.6Sr0.4Co0.8Fe0.2O3 oxides are considered to be acceptable as mixed conducting component in composite cathode designs together with doped ceria electrolytes.

关键词： electrical conduction Perovskites thermal expansion

Identifying cancer genes from cancer mutation profiles by cancer functions

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Science China(Life Sciences) 2008年第6期51卷 569-574页

作者： LI YanHui1, GUO Zheng1,2, PENG ChunFang2, LIU Qing2, MA WenCai2, WANG Jing2, YAO chen2, ZHANG min2 & ZHU Jing1 1 Bioinformatics Centre, School of Life Science, University of Electronic Science and Technology of China, chengdu 610054, China 2 School of Bioinformatics Science and Technology, Harbin Medical University, Harbin 150086, China Bioinformatics Centre School of Life Science University of Electronic Science and Technology of China Chengdu China School of Bioinformatics Science and Technology Harbin Medical University Harbin China

It is of great importance to identify new cancer genes from the data of large scale genome screenings of gene mutations in cancers. Considering the alternations of some essential functions are indispensable for oncogenesis, we define them as cancer functions and select, as their approximations, a group of detailed functions in GO (Gene Ontology) highly enriched with known cancer genes. To evaluate the efficiency of using cancer functions as features to identify cancer genes, we define, in the screened genes, the known protein kinase cancer genes as gold standard positives and the other kinase genes as gold standard negatives. The results show that cancer associated functions are more efficient in identifying cancer genes than the selection pressure feature. Furthermore, combining cancer functions with the number of non-silent mutations can generate more reliable positive predictions. Finally, with precision 0.42, we suggest a list of 46 kinase genes as candidate cancer genes which are annotated to cancer functions and carry at least 3 non-silent mutations.

关键词： mutation profile cancer gene Gene Ontology gene function prediction

Application of L-thiazolidine-4-carboxylic acid monolayer in electrochemical determination of copper(Ⅱ)

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Science China Chemistry 2010年第1期53卷 257-262页

作者： CUI Xin1,FU YingZi1,2,LI MiaoSi1,chen min2,HE Xuan1,LIU XiaoHua1 & FENG Xiaoming1 1Key Laboratory of Green Chemistry & Technology,ministry of Education College of Chemistry,Sichuan University,chengdu 610064,China 2Key Laboratory of Luminescence and Real-Time Analysis,ministry of Education College of Chemistry and Chemical Engineering,Southwest University,Chongqing 400715,China Key Laboratory of Green Chemistry & Technology Ministry of Education College of Chemistry Sichuan University Chengdu China Key Laboratory of Luminescence and Real-Time Analysis Ministry of Education College of Chemistry and Chemical Engineering Southwest University Chongqing China

L-Thiazolidine-4-carboxylic acid monolayer was prepared on gold electrodes through the self-assembly *** novel thioether-based monolayer could efficiently preconcentrate Cu2+,which provided a simple,stable and reproducible method for the determination of Cu2+.The modified electrodes were stable enough to be continuously used for one week(more than 30 times regeneration) with lower than 10% decrease in the *** retained their initial activity for more than one month if used once a *** calibration curve was linear for Cu2+ from 0.6 to 158.8 μg L?1 with a detection limit of 0.38 μg L?*** relative standard deviation was 3.2% for a series of six successive *** proposed method was applied in the determination of Cu2+ in mineral water and human hair samples.

关键词： L-thiazolidine-4-carboxylic acid copper ions gold electrode thioether monolayer

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一种高效气动弹性虚拟仿真建模技术研究

系统仿真学报 2011年第6期23卷 1073-1076页

作者：姚伟刚徐敏陈志敏西北工业大学航天学院西安710072 西北工业大学航空学院西安710072

采用特征正交分解(POD,Proper Orthogonal Decomposition)方法,建立了基于状态空间的非定常气动力模型,耦合结构方程,建立了降阶的气动弹性系统,开展了气动弹性虚拟仿真研究,与CFD/CSD全耦合相比,效率提高了2～3个数量级。具体过程是:... 详细信息

采用特征正交分解(POD,Proper Orthogonal Decomposition)方法,建立了基于状态空间的非定常气动力模型,耦合结构方程,建立了降阶的气动弹性系统,开展了气动弹性虚拟仿真研究,与CFD/CSD全耦合相比,效率提高了2～3个数量级。具体过程是:首先获取全阶系统的频域快照构成POD核,通过对POD核进行奇异值分解提取POD模态(或POD基),对低能量模态截断形成降阶子空间,并将其映射到全阶系统,从而形成基于状态空间的降阶的非定常气动力模型。对气动弹性标模AGARD445.6进行算例验证,证明了降阶方法正确,可以提供高效、高精度的气动弹性分析。

关键词：特征正交分解降阶模型颤振系统仿真

Is the Cape Stone Forest in Shantou City formed by wave erosion? A comparison of the pedestal rocks on the coasts and the mountains of Queshi in eastern Guangdong, China

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Journal of Mountain Science 2024年第5期21卷 1447-1463页

作者： chen min WANG Wei School of Geography South China Normal UniversityGuangzhou 510631China

Cape Stone Forest is a group of granite rock pillars(pedestal rocks) towering over Shilin Lake, on the southern shore of Shantou Bay in eastern Guangdong, China. The rock pillars were previously identified as sea stacks because they have marine notch-like concave sidewalls at their base, and more importantly, the lake is immediately adjacent to the bay, which is exposed to the open sea. However, rock pillars similar in shape and size can also be found at the top of Queshi Mountain, which is only about 300 meters northwest of the lake and about 85 meters above sea level. Therefore, the marine origin of Cape Stone Forest is seriously questioned. In this study, 3D imagery and drone technology were used to collect data in the investigations without direct manual measurements in the water or on the mountain. It shows that the concave sidewalls of the rock pillars in the lake and on the mountains occur at different heights and are exposed to different directions, while a natural sea stack on Mayu Island at the mouth of Shantou Bay has a horizontal notch parallel to the sea level, although the granite rock of the sea stack is the same as that of the lake and the mountains. The eastern side of the island, where the sea stack is located, is exposed to the open sea but blocks large waves for the rock pillars in the lake. Therefore, the origin of Cape Stone Forest cannot be explained by wave-based mechanisms. The only satisfactory explanation that takes into account all the field evidence is that the narrow rock pillars of the lake and mountain were formed by chemical weathering that penetrated closely the spaced joints of the granite rock, and the notch-like concave sidewalls were formed by more effective chemical weathering at the base of the pillars.

关键词： Pedestal rock Granite Closely spaced joints Wave erosion Chemical weathering

Insights into carbon dioxide sequestration into coal seams through coupled gas flow-adsorption-deformation modelling

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 26-40页

作者： Hywel Thomas min chen Geoenvironmental Research Centre Cardiff School of EngineeringCardiff UniversityQueen’s BuildingsThe ParadeNewport RoadCardiffCF243AAUK Key Laboratory of Marine Geology Tongji UniversityShanghai200092China

Injecting carbon dioxide(CO_(2))into coal seams may unlock substantial carbon sequestration *** the coal acts like a carbon filter,it can preferentially absorb significant amounts of CO_(2).To explore this further,desorption of the adsorbed gas due to pressure drop is investigated in this paper,to achieve an improved understanding of the long-term fate of injected CO_(2) during post-injection *** paper presents a dual porosity model coupling gas flow,adsorption and geomechanics for studying coupled processes and effectiveness of CO_(2) sequestration in coals.A new adsorption?desorption model derived based on thermodynamics is incorporated,particularly,the desorption hysteresis is *** reliability of the proposed adsorption-desorption isotherm is examined via validation *** is indicated that occurrence of desorption hysteresis is attributed to the adsorption-induced pore *** injection ceases,the injected gas continues to propagate further from the injection well,while the pressure in the vicinity of the injection well experiences a significant *** the adsorbed gas near the well also decreases,this decrease is less compared to that in pressure because of desorption *** unceasing spread of CO_(2) and drops of pressure and adsorbed gas depend on the degree of desorption hysteresis and heterogeneity of coals,which should be considered when designing CO_(2) sequestration into coal seams.

关键词： CO_(2)geological storage Coal seam Adsorption Desorption hysteresis

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乌梅丸汤剂临床应用举隅

世界中西医结合杂志 2018年第1期13卷 138-141页

作者：俞翔陈敏北京中医药大学附属护国寺中医院北京100035 中国科学院心理研究所北京100010

乌梅丸为《伤寒论》经典名方,组方精妙,寒温并用,攻补兼施,被后世医家广泛应用于临床各科。现代医家,亦沿用清代的认识,将其广泛应用于各种病证。当代著名中医学家蒲辅周就认为:"乌梅丸组方体现了张仲景所说:‘肝之病,补用酸,助用焦苦,... 详细信息

乌梅丸为《伤寒论》经典名方,组方精妙,寒温并用,攻补兼施,被后世医家广泛应用于临床各科。现代医家,亦沿用清代的认识,将其广泛应用于各种病证。当代著名中医学家蒲辅周就认为:"乌梅丸组方体现了张仲景所说:‘肝之病,补用酸,助用焦苦,益用甘味之药调之。’和《难经》:‘见肝之病……先实其脾气,无令得受肝之邪’的理论。乌梅丸非只为蛔厥而设,乃为厥阴诸病之主方。"乌梅丸有两个作用,一是治厥阴病的寒热错杂证,另一是治蛔厥。乌梅丸在临床中治疗寒热错杂,阴阳失调,虚实夹杂之厥阴病,有非常好的疗效。

关键词：乌梅丸伤寒论临床应用

Polyolefin vitrimers bearing acetoacetate functionality

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Science China Chemistry 2024年第11期67卷 3861-3867页

作者： Zihao Wang Yue Liu Wenmin Pang Ao chen min chen Chinese Academy of Sciences (CAS) Key Laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering University of Science and Technology of China Institutes of Physical Science and Information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education Anhui University

Polyolefin vitrimers are polymer networks bearing reversible covalent crosslinking points, enabling them to be reprocessed and recycled. In this contribution, a series of polyolefin vitrimers were designed based on the acetoacetate-functionalized polyolefin copolymers, which were produced through the direct copolymerization of ethylene with polar comonomers using a phosphinesulfonate palladium catalyst. The pendant acetoacetate group could mediate several characteristic reactions, such as the Michael addition reaction, ketone-amine condensation and metal coordination reaction. As such, structurally adjustable polyolefin vitrimers can be accessed by introducing various dynamic crosslinking bonds, including disulfide exchange, transamination of vinylogous urethane and labile metal coordination bond. The utilization of different crosslinking reactions and the mole ratio of crosslinkers significantly impact the material properties of the resultant polymers. Specifically, the generated polyolefin vitrimers demonstrated excellent reprocessability and closed-loop recycling properties. The study in this work provides an efficient strategy to access various polyolefin vitrimers.

关键词： polyolefin vitrimers acetoacetate group polar monomer olefin copolymerization

Short-time maritime target detection based on polarization scattering characteristics

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Journal of Systems Engineering and Electronics 2024年第1期35卷 55-64页

作者： chen Shichao LUO Feng TIAN min LYU Wanghan College of Computer and Information Engineering(College of Artificial Intelligence) Nanjing Tech UniversityNanjing 211816China Hangzhou Institute of Technology Xidian UniversityHangzhou 311200China

In this paper,a detection method combining Cameron decomposition based on polarization scattering characteristics in sea clutter background is ***,the Cameron decomposition is exploited to fuse the radar echoes of full polarization channels at the data *** to the artificial material structure on the surface of the target,it can be shown that the non-reciprocity of the target cell is stronger than that of the clutter ***,based on the analysis of the decomposition results,a new feature with scattering geometry characteristics in polarization domain,denoted as Cameron polarization decomposition scattering weight(CPD-SW),is extracted as the test statistic,which can achieve more detailed descriptions of the clutter scattering characteristics utilizing the difference between their scattering ***,the superiority of the proposed CPD-SW detector over traditional detectors in improving detection performance is verified by the IPIX measured dataset,which has strong stability under short-time observation in threshold detection and can also improve the separability of feature space zin anomaly detection.

关键词： sea clutter small target radar detection Cameron decomposition characteristics analysis