金顶超大型铅锌矿喷流沉积成因初探

云南兰坪金顶铅锌矿床是我国规模最大的铅锌矿床,伴生的银、镉、铊、硫铁矿、天青石、石膏等也有很高的工业价值。目前,对其成因有较大的争论,多数人支持沉积-改造观点。笔者根据所收集的资料与研究,初步提出了陆相喷流沉积成因的认识。进一步的研究工作正在继续进行。

愿与天下共温凉 访省政协委员、鑫东森集团有限公司董事长洪顶超

坚守实业30年,担任政协委员15年,参与香港社团活动20年,投身慈善事业30年……面对记者,省政协委员、鑫东森集团有限公司董事长洪顶超始终面带微笑侃侃而谈,言语中透出历经风雨后的从容、淡定与自信。从一块布做起“我是做纺织品出身的,一干就是30年。”洪顶超出生于福建晋江,后迁居香港,20世纪90年代中期回到厦门投资办厂,心无旁骛做实业。

Ultrastructural Changes of Scolex on Cysticercus pisiformis during Relative Rest and Motion States

[Objective] This study aimed to research the ultra-morphological changes of scolex of Cysticercus pisiformis during the relative rest and motion states. [Method] The ultrastructure changes of scolex located in cyst and evaginated from cyst after cultivation were comparatively observed by scanning electron microscope. [Result] When the scolex was in the relative rest state, observed from the top, the rostel um with the tegument muscular column that connected to tooth-hook looked like the umbrel a and covered on the front end of the scolex. Viewed from the side of the scolex, the tooth-hook on the rostel um looked like the antler branch and had only one row. Four suckers looked like cavities, and were located in the back of the rostel um and distributed around the scolex in the equidistance. When the scolex was in the motion states, the tegument muscular column on the rostel um contracted, the antler-like tooth-hook extended to periphery, and the sucker also made the ring-like and longitudinal-like contraction. [Conclusion] Ultrastructure of the scolex of C. pisiformis changed apparently during relative rest and motion states. Those changes help scolex to invade the host tissue.

川中地区三叠系中、下统地震相与沉积相研究

应用碎屑岩地震相研究的理论和方法,对川中地区三叠系中、下统碳酸盐岩地震相进行了研究。地震相与沉积相的结合,通过地震剖面提供的各种参数解释环境背景和岩相条件,根据地震剖面上所通过的钻井岩相划分,使地震相、沉积相、钻井岩相分析融为一体,并在沉积和岩相研究方法上探索新的途径。

Ultrastructure Features of Sperm Cell in Amaryllis vittata

Ultrastructure of sperm cells in pollen tube of Amaryllis vittata Ait. has been investigated in details by electron microscopy ,with particular emphasis on the organization and distribution of microtubules.The two newly formed sperm cells are arranged in tandem and sometimes in transverse at the right angle to the long axis of the pollen tube.Thevegetative nucleus is ahead and closely associated with the two sperm cells in all examined pollen tubes. The microtubules are distributed in the region between the common cell wall and the proximity of the sperm nucleus,they are singles and dispersed with mainly orientation of longitudinal and oblique,forming a loose bucket-like structure as a whole.In late stage of development,all of the microtubule array longitudinally and enclose the sperm nucleus.This configuration is very similar to the basket-like structure of microtubule in the generative cell. These results show that the organization and distribution of microtubules in the sperm cells are dynamic during cell development.

Ultrastructural Changes of Vegetative Cells in Amaryllis Pollen during Its Germination

Structural and organizational changes of the vegetative cell in Amaryllis vittata Ait. during such dynamic processes of pollen as hydration, activation and germination have been examined with electron microscopy. The mature pollen grain is composed of such organelles as plastids, mitochondria,endoplasmic reticulum, dictyosomes and lipid bodies which are in their resting state. Microfilaments appear as aggregates. After pollen activation, however,the organelles undergo great changes in number and shape: the lamellae of plastids and the cristae of mitochondria increase conspicuously in number, the cisternae of the endoplasmic reticulum become narrower; the dictyosomes produce vesicles actively the lipid bodies become degraded and the microfilament aggregates disperse. Cortical microtubules and spiny vesicles appear in the cytoplasm after germination of the pollen tube. No apparent structural changes of the organelles were noticed any longer during this period and microfilaments are distributed throughout the entire pollen tube as a three-dimensional network.

Ultrastructure and Protein Composition Changes during Acrosome Reaction in the Sperm of Chinese Shrimp, Fenneropenaeus Chinensis

Egg water was used to induce acrosome reaction in mature sperm of Fenneropenaeus chinensis .Transmission electron microscope and SDS PAGE were used to study the ultrastructure and protein changes of the sperm in F.chinensis ,which has undergone acrosome reaction.The results demonstrated that the sperms from female thelycum could be induced acrosome reaction in vitro by egg water,which was a kind of egg jelly released from oocyte into seawater during oocyte activation.More than fifty percent of sperm finished acrosome reaction during the first 30 min, in vitro .The whole event consists of the retraction of the spike and acrosome exocytosis.Spike was retracted and fused to acrosome cap followed by the release of acrosome granules.When the original egg water was diluted 5 and 10 times,The diluted egg water also have the ability to induce sperm acrosome reaction,but the acrosome reaction rate is much lower than that of the original egg water in the same time.Capillary zone electrophoresis was used to detect the biochemical components of egg water.Egg water was composed of two different components,which were also demonstrated by SDS PAGE.The molecular weights of the two kinds of egg jellies are both about 200kDa.Gelatin substrate SDS PAGE results did not show any hydrolytic enzyme activity in egg water.After acrosome reaction,many sorts of proteins in sperm are degraded.When the reacted sperms were examined with gelatin substrate SDS PAGE,there were six major peptide bands with hydrolytic enzyme activity were detected.Their molecular weights are 200kDa,130 kDa,66 kDa,53 kDa,48 kDa and 41 kDa respectively.These hydrolases cannot be detected in the sperms before acrosome reaction.The acrosome reaction of Chinese shrimp, F.chinensis is much different to that of the sperm in the shrimp, Sicyonia ingentis ,which the acrosome reaction was clearly studied.There is not filament formation during the acrosome reaction in Chinese shrimp.The time of exocytosis in the sperm of Chinese shrimp is also much longer than that of the sperm of Sicyonia ingentis .

Key technologies and equipment for a fully mechanized top-coal caving operation with a large mining height at ultra-thick coal seams

Thick and ultra-thick coal seams are main coal seams for high production rate and high efficiency in Chinese coal mines, which accounts for 44 % of the total minable coal reserve. A fully mechanized top-coal caving mining method is a main underground coal extraction method for ultra-thick coal seams. The coal extraction technologies for coal seams less than 14 m thick were extensively used in China. However, for coal seams with thickness greater than 14 m, there have been no reported cases in the world for underground mechanical extraction with safe performance, high efficiency and high coal recovery ratio. To deal with this case, China Coal Technology ＆ Engineering Group, Datong Coal Mine Group, and other 15 organizations in China launched a fundamental and big project to develop coal mining technologies and equipment for coal seams with thicknesses greater than 14 m. After the completion of the project, a coal extraction method was developed for top-coal caving with a large mining height, as well as a ground control theory for ultra-thick coal seams. In addition, the mining technology for top-coal caving with a large mining height, the ground support technology for roadway in coal seams with a large cross-section, and the prevention and control technology for gas and fire hazards were developed and applied. Furthermore, a hydraulic support with a mining height of 5.2 m, a shearer with high reliability, and auxiliary equipment were developed and manufactured. Practical implication on the technologies and equipment developed was successfully completed at the No. 8105 coal face in the Tashan coal mine, Datong, China. The major achievements of the project are summarized as follows： 1. A top-coal caving method for ultra-thick coal seams is proposed with a cutting height of 5 m and a top-coal caving height of 15 m. A structural mechanical model of overlying strata called cantilever beam-articulated rock beam is established. Based on the model, the load resistance of the hydraulic support with a large mining height for top-coal caving method is determined. With the analysis, the movement characteristics of the top coal and above strata are evaluated during top-coal caving operation at the coal face with a large mining height. Furthermore, there is successful development of comprehensive technologies for preventing and controlling spalling of the coal wall, and the top-coal caving technology with high efficiency and high recovery at the top-coal caving face with a large mining height. This means that the technologies developed have overcome the difficulties in strata control, top-coal caving with high efficiency and high coal recovery, and enabled to achieve a production rate of more than 10 Mtpa at a single top-coal caving face with a large mining height in ultra-thick coal seams; 2. A hydraulic support with 5.2 m supporting height and anti-rockburst capacity, a shearer with high reliability, a scraper conveyor with a large power at the back of face, and a large load and long distance headgate belt conveyor have been successfully developed for a top-coal caving face with large mining height. The study has developed the key technologies for improving the reliability of equipment at the coal face and has overcome the challenges in equipping the top-coal caving face with a large mining height in ultra-thick coal seams; 3. The deformation characteristics of a large cross-section roadway in ultra-thick coal seams are discovered. Based on the findings above, a series of bolt materials with a high yielding strength of 500-830 MPa and a high extension ratio, and cable bolt material with a 1 × 19 structure, large tonnage and high extension ratio are developed. In addition, in order to achieve a safe roadway and a fast face advance, installation equipment for high pre-tension bolt is developed to solve the problems with the support of roadway in coal seams for top-coal caving operation with a large mining height; 4. The characteristics of gas distribution and uneven emission at top-coal caving face with large mining height in ultra-thick coal seams are evaluated. With the application of the technologies of gas drainage in the roof, the difficulties in gas control for high intensive top-coal caving mining operations, known as ＂low gas content, high gas emission＂, are solved. In addition, large flow-rate underground mobile equipment for making nitrogen are developed to solve the problems with fire prevention and safe mining at a top-coal caving face with large mining height and production rate of more than 10 Mtpa. A case study to apply the developed technologies has been conducted at the No. 8105 face, the Tashan coal mine in Datong, China. The case study demonstrates that the three units of equipment, i.e., the support, shearer and scraper conveyor, are rationally equipped. Average equipment usage at the coal face is 92.1%. The coal recovery ratio at the coal face is up to 88.9 %. In 2011, the coal production at the No. 8105 face reached 10.849 Mtpa, exceeding the target of 10 Mtpa for a topcoal caving operation with large mining height performed by Chinese-made mining equipment. The technologies and equipment developed provide a way for extracting ultra-thick coal seams. Currently, the technologies and equipment are used in 13 mining areas in China including Datong, Pingshuo, Shendong and Xinjiang. With the exploitation of coal resources in Western China, there is great potential for the application of the technologies and equipment developed.

Test and application of hydraulic expansion bolts in a roadway under goaf with ultra-close separation

The roof of a roadway under goal with ultra-close separation consists of thin rock strata and rocks caving in upper goal. Influenced by the mining of the upper coal seam, the roof is loose and broken, and its integ- rity is poor. Resin anchored bolts cannot provide an effective anchoring force in such roof conditions. By conducting free expansion tests and field pull-out tests on a hydraulic expansion bolt, this study has ana- lyzed the influencing factors and laws of radial expansion and anchoring force changes in the rod body. This has revealed the anchoring mechanism of such bolts, and has obtained reasonable water injection pressures and suitable drilling diameters （which are 20-25 MPa and 32-35 mm respectively） for the hydraulic expansion bolt （cR28 mm） used in these tests. Based on pull-out tests at different interlayer spacing, the applicability of hydraulic expansion bolts had been verified for controlling the roof of road- ways under goal with ultra-close distance. Combined with the deformation and failure characteristics of the test roadway roof, this paper proposes a united roof-control technology based on the use of hydraulic expansion bolts and advancing intubation for the roof. Engineering practice indicated that the roof of the test roadway did not generate leaking and caving phenomenon, and the amount of roof deformation was controlled to within 150 mm. Maintenance of the roadway roof has been improved significantly, which ensures safe mining in coal seams with ultra-close separation.

Super-connected and Hyper-connected Cubic Bi-Cayley Graphs

Let G be a finite group and let S（possibly, contains the identity element） be a subset of G. The Bi-Cayley graph BC（G, S） is a bipartite graph with vertex set G × { 0,1} and edge set {（g, 0） （sg,1） ： g∈ G, s ∈ S}. A graph is said to be super-connected ff every minimum vertex cut isolates a vertex. A graph is said to be hyper-connected if every minimum vertex cut creates two components, one of which is an isolated vertex. In this paper, super-connected and/or hyper-connected cubic Bi-Cayley graphs are characterized.

马克·力文:我不说中文,但我讲中国故事

台上的马克？力文颇为醒目,戴着一顶超大号的宽檐帽,留着一大把灰白色络腮胡,亮色的格子衬衣外罩了一件黑色马甲,一把吉他始终跟在身旁。他憨憨一笑,露出一排白牙。1948年出生于洛杉矶的马克？力文今年已经68岁了,一直致力于在和平与友谊间搭建桥梁。他是社会学博士、美国乡村音乐人、慈善事业的组织者、专栏作家。目前,马克在中央民族大学任教,

Vertex Representations of Toroidal Special Linear Lie Superalgebras

Based on the loop-algebraic presentation of 2-toroidal Lie superalgebras, a free field representation of toroidal Lie superalgebras of type A(m, n) is constructed using both vertex operators and bosonic fields.

Structural phase transition, antiferromagnetism and two superconducting domes in LaFeAsO_(1-x)F_x(0

We report^(75) As nuclear magnetic resonance(NMR)/nuclear quadrupole resonance(NQR) and transmission electron microscopy(TEM) studies on LaFeAsO_(1-x)F_x. There are two superconducting domes in this material. The first one appears at 0.03 ≤ x ≤0.2 with T_c^(max) = 27 K, and the second one at 0.25 ≤x≤0.75 with T_c^(max) = 30 K. By NMR and TEM, we demonstrate that a C4-to-C2 structural phase transition(SPT) takes place above both domes, with the transition temperature T_s varying strongly with x. In the first dome, the SPT is followed by an antiferromagnetic(AF) transition, but neither AF order nor low-energy spin fluctuations are found in the second dome. By ^(75) As nuclear spin-lattice relaxation rate(1/T_1) measurements, we find that AF order and superconductivity coexist microscopically in LaFeAsO_(0.97) F_(0.03). In the coexisting region, 1/T_1 decreases at T_c but becomes proportional to T below 0.6 T_c, indicating gapless excitations. Therefore, in contrast to the early reports, the obtained phase diagram for x ≤ 0.2 is quite similar to the doped BaFe_2As_2 system. The electrical resistivity p in the second dome can be fitted by ρ = ρ0 + AT^n with n = 1 and a maximal coefficient A at around xopt = 0.5-0.55 at which T_s extrapolates to zero and Tc is the maximal, which suggests the importance of quantum critical fluctuations associated with the SPT. We have constructed a complete phase diagram of LaFeAsO_(1-x)F_x, which provides insight into the relationship between SPT, antiferromagnetism and superconductivity.

Study of mode transformation and energy attenuation of wedge waves with different apex angles by laser ultrasonic techniques

This research focuses on measuring the mode transformation and energy attenuation of wedge waves for different apex angle wedges by using laser ultrasound techniques.Pulsed laser excitation and optical deflection beam methods for detection were used to measure the wedge waves.In experiment,various wedge waves at different locations were recorded by scanning the excitation laser along the wedge tip,and different orders of wedge waves were observed.By fixing the distance between the excitation and detection positions and scanning the samples along the direction normal to the wedge tip,the modes transformation process was obtained.It was found that the energy of the acoustic waves for 20°,25° and 30° wedges decreased exponentially to a steady energy of Rayleigh wave within the main wavelength range of the acoustic modes,while the energy of acoustic waves of 45° and 60° wedge remained stable as the propagation line was scanned away from the wedge tip.