二十世纪末的世界原铝工业

阐述了本世纪末全球原铝工业的现状、技术发展水平和在环境保护方面取得的进步 ,系统地介绍了世界原铝的生产能力、供求状况 ,以及生产成本和价格对铝工业的影响 。

Chalcogen heteroatoms doped nickel-nitrogen-carbon single-atom catalysts with asymmetric coordination for efficient electrochemical CO_(2) reduction

The electronic configuration of central metal atoms in single-atom catalysts(SACs)is pivotal in electrochemical CO_(2) reduction reaction(eCO_(2)RR).Herein,chalcogen heteroatoms(e.g.,S,Se,and Te)were incorporated into the symmetric nickel-nitrogen-carbon(Ni-N_(4)-C)configuration to obtain Ni-X-N_(3)-C(X:S,Se,and Te)SACs with asymmetric coordination presented for central Ni atoms.Among these obtained Ni-X-N_(3)-C(X:S,Se,and Te)SACs,Ni-Se-N_(3)-C exhibited superior eCO_(2)RR activity,with CO selectivity reaching~98% at-0.70 V versus reversible hydrogen electrode(RHE).The Zn-CO_(2) battery integrated with Ni-Se-N_(3)-C as cathode and Zn foil as anode achieved a peak power density of 1.82 mW cm^(-2) and maintained remarkable rechargeable stability over 20 h.In-situ spectral investigations and theoretical calculations demonstrated that the chalcogen heteroatoms doped into the Ni-N_(4)-C configuration would break coordination symmetry and trigger charge redistribution,and then regulate the intermediate behaviors and thermodynamic reaction pathways for eCO_(2)RR.Especially,for Ni-Se-N_(3)-C,the introduced Se atoms could significantly raise the d-band center of central Ni atoms and thus remarkably lower the energy barrier for the rate-determining step of ^(*)COOH formation,contributing to the promising eCO_(2)RR performance for high selectivity CO production by competing with hydrogen evolution reaction.

Polygynous Mating System and Behavioural Reason of Black Crested Gibbon (Nomascus concolor jingdongensis) at Dazhaizi,Mt.Wuliang, Yunnan,China

The field research on five black crested gibbon groups, recently performed at Dazhaizi, Mr. Wuliang, Central Yunnan, China, showed that all groups in the local population consisted of one adult male, two adult females and 2 - 5 sub-adults, juveniles and itfants. The mean group size was 6.2 in August 2003 and 6.4 in August 2005. Two subadult males disappeared from their natal home range and three newborns were given birth in Group 3 （G3） and G4 during this study. The two adult females in G1, G2 and G3 gave births and/or carried babies but at different times. There was no aggressive or dominating behaviour observed between the two adult females. One floating female was first seen in G3＇s territory on April 15, 2005. The two resident females interrupted her duet with adult male and chased her. We did not observe adult male chased this floating female and she left G3＇s territory 10 days later. Sub-adult males often kept distance with the family, and they often sang solo bouts in their natal territory before they dispersed. The sub-adult males and females dispersed from natal territory and two adult resident females rejected the third one, which might were the reasons why the black gibbon groups were polygyny in Dazhaizi.

Synthesis and Crystal Structure of t he Complex of Antimony Trichloride and Dioxane

New solid complex of the antimony trichloride and dioxane was obtained th rough a reaction of the dioxane and the absolute methanol solution of the antimony trichloride.The formula of the complex is[SbCl_(3)·{(CH_(2))_(4)O_(2)}_(1.5)].The crystal structure of the comple x belongs to cubic system,space group I-43d,a=17.1417(5)?,Z=16.The trivalent antimony ion not only bonds directly to three chlorine anions,but also is co ordinated by three oxygen atoms of th e dioxane molecules.Two oxygen atoms in a dioxane molecule wi ll coordinate to different antimony ions,respectively.

Microwave Assisted Synthesis of a New Triplet Iridium（Ⅲ） Pyrazine Complex

A new cyclometalated iridium（IlI） complex Ir（DPP）3 （DPP=2,3-diphenylpyrazine） was prepared by reaction of DPP with iridium trichloride hydrate under microwave irradiation. The structure of the complex was confirmed by elemental analysis, ^1H NMR, and mass spectroscopy. The UV-Vis absorption and photoluminescent properties of the complex were investigated. The complex shows strong ^1MLCT （singlet metal to ligand charge-transfer） and aMLCT （triplet metal to ligand charge-transfer） absorption at 382 and 504 nm, respectively. The complex also shows strong photoluminescence at 573 nm at room temperature. These results suggest the complex to be a promising phosphorescent material.

Ocean-bottom cable data multiple suppression based on equipoise pseudo-multichannel matching filter

The effect of strong reflection interfaces, such as free surface, seabed, is strong; thus, the coupling of multiples and waves reduces the quality of ocean-bottom cable seismic data. Using the different polarity response of hydrophones and geophones to downgoing wave fields, dual-sensor summation can eliminate receiver-side multiples, enhance primaries, and improve the resolution of seismic data. We present a dual-sensor summation method based on the equipoise pseudo-multichannel adaptive matching filter. Compared with traditional methods, the proposed method is totally data driven and does not depend on the reflection coefficient; moreover, good results are obtained using synthetic and real data.

A method for calculation of ion distribution in reaction system forming hydroxide

A formula was proposed to calculate the distribution of metal ions quantitatively in chemical reaction system forming hydroxide where precipitation and complex are formed together. The effects of some factors on formation of precipitation and complex were investigated, and the corresponding precipitation rates of zinc, iron （III）, aluminum, copper and magnesium were calculated. As a result, it shows that the proposed formula is reliable. By the proposed formula, the existence state of metal ions in hydroxides reaction system with any metal ions can be well described and the effects of some factors on the distribution of metal ions were determined.

Synthesis, crystal structure and magnetic properties of novel copper compound Cu(phen)(m-CBA)_2

A novel compound Cu（phen）（m-CBA）2 was synthesized with m-chlorobenzoic acid（m-CBA）, 1,10-phenanthroline（phen） and Cu（OAc）2·H2O. It was characterized by IR, UV, elemental analyses and X-ray crystallography. It crystallizes in the monoclinic crystal system with C2/c space group, a=2.9699（4） nm, b=1.15452（2） nm, c=1.5335（2） nm, β=111.118（2）°, V=4.905 1（1） nm3, Z=8, F（000）=2 328, R1=0.072 8, wR2=0.223 4 [I2σ（I）]. Structure analysis shows that the copper center coordinates with two nitrogen atoms from one 1,10-phenanthroline molecule, two oxygen atoms from two m-chlorobenzoic acid molecules, giving a distorted squared planar coordination geometry. This novel compound shows paramagnetic interactions between copper centers.

Advances in Small RNAs and Sexual Reproduction in Plants

Small RNAs are non-coding RNA molecules with 20-30 nucleotides （nt） in length that mainly play regulatory roles in gene expression at the post-transcription level by directly cutting target mRNA or inhibiting its translation. Small RNAs play regulatory roles in the growth and development process of plants at the core of gene regulatory networks, which has been widely studied and confirmed in sporophyte generation of plants. However, few researches have been conducted on small RNAs and gametophyte generation. It is reported that small RNAs play important roles in floral organ development, gametogenesis, fertilization, and early zygotic development of plants. In addition, various small RNAs also play roles in controlling genetic integrity, cell differentiation and functions during the sexual reproduction process of plants. However, most of the specific functions of small RNAs in the sexual reproduction process are unknown yet. This study mainly aimed to introduce small RNAs in plants, summarize the latest advances in researches of small RNAs and plant sexual reproduction, and make prospect on its future.

Generating test cases for software configuration testing

Software configuration testing is used to test a piece of software with all kinds of hardware to ensure that it can run properly on them. This paper generates test cases for configuration testing with several common methods, such as multiple single-factor experiments, uniform design, and orthogonal experiment design used in other fields. This paper analyzes their merits and improves the orthogonal experiment design method with pairwise testing, and decreases the testing risk caused by incomplete testing with a method of multiple-factors-covering. It presents a simple factor cover method which can cover all the factors and pairwise combinations to the greatest degree. Some comparisons of these methods are made on the aspects of test suite scale, coverage, and usability, etc..

Synthesis and luminescent properties of ternary complexes of terbium with thenoyltrifluoroacetone and reactive ligand

Three new reactive ternary terbium complexes were synthesized with the first ligand of thenoyltri-(fluoroacetone) and the reactive secondary ligand such as maleic anhydride, undecenoic acid, oleic acid, and characterized by means of elemental analysis, ethylenediamine tetraacetic acid titrimetric method, Fourier transform infrared and ultraviolet spectroscopies. And the luminescent properties of the ternary terbium complexes were investigated. The results show that the ternary terbium complexes possess much higher luminescent intensity than the binary complex of terbium with thenoyltrifluoroacetone, and the synergy ability sequence of the three reactive ligands is as follows: undecenoic acid>oleic acid>maleic anhydride. Because the ternary terbium complexes contain reactive (ligands) that can be copolymerized with other monomers, a new way for the synthesis of the bonding-type rare earth polymer functional materials with excellent luminescent properties is provided.

Cross Point Assignment Algorithm Under Consideration of Very Long Nets

A cross point assignment algorithm is proposed under consideration of very long nets (LCPA).It is to consider not only the cost of connection between cross points and pins and the exclusive cost among cross points on the boundary of a global routing cell,but also the cost of displacement among cross points of the same net.The experiment results show that the quality and speed in the following detailed routing are improved obviously,especially for very long nets.

Effects of synthesis temperature and raw materials composition on preparation of β-Sialon based composites from fly ash

β-Sialon based composites were successfully prepared from fly ash and carbon black under nitrogen atmosphere by carbothermal reduction-nitridation process. Effects of heating temperature and raw materials composition on synthesis process were investigated, and the formation process of the composites was also discussed. The phase composition and microstructure of the composites were characterized by X-ray diffraction and scanning electronic microscopy. The results show that increasing heating temperature or mass ratio of carbon black to fly ash can promote the formation of β-Sialon. The β-Sialon based composites can be synthesized at 1723 K for 6 h while heating the sample with mass ratio of carbon black to fly ash of 0.56. The as-received β-Sialon in the composites exists as granular with an average particle size of 2-3 μm. The preparation process of β-Sialon based composites includes the formation of O′-Sialon, X-Sialon and β-Sialon as well as the conversion processes of O′-Sialon and X-Sialon to β-Sialon.

Ontology-based schema matching method in web query interface integration

Deep web data integration needs to do schema matching on web query interfaces and obtain the mapping table.By introducing semantic conflicts into web query interface integration and discussing the origins and categories of the semantic conflicts,an ontology-based schema matching method is proposed.The process of the method is explained in detail using the example of web query interface integration in house domain.Conflicts can be detected automatically by checking semantic relevance degree,then the categories of the conflicts are identified and messages are sent to the conflict solver,which eliminates the conflicts and obtains the mapping table using conflict solving rules.The proposed method is simple,easy to implement and can be flexibly reused by extending the ontology to different domains.

Accuracy Analysis of Assembly Success Rate with Monte Carlo Simulations

Monte Carlo simulation was applied to Assembly Success Bate (ASK) analyses. ASR of two peg-in-hole robot assemblies was used as an example by taking component parts' sizes, manufacturing tolerances and robot repeatability into account. A statistic arithmetic expression was proposed and deduced in this paper, which offers an alternative method of estimating the accuracy of ASR, without having to repeat the simulations. This statistic method also helps to choose a suitable sample size, if error reduction is desired. Monte Carlo simulation results demonstrated the feasibility of the method.

Syntheses, Characterization and Magnetism of μ-2-Chloroterephthalato Nickel (Ⅱ) Binuclear Complexes

Three new nickel(Ⅱ) binuclear complexes, namely,[Ni_2(CTPHA)(Phen)_4](ClO_4)2·4H_2O (complex 1 ), [Ni_2(CTPHA) (Nphen)_4](ClO_4)_2·2H_2O(complex 2 ) and [Ni2 (CTPHA)(Bpy)4] (ClO4)2 (complex 3 ). (CTPHA = 2-chloroterephthalate . Phen=1, 10-phenanthroline, Nphen=5-nitro-1, 10-phenanthroline, Bpy=2, 2-bipyridyl), have been synthesized and characterized by elemental analysis, IR, molar conductance and electronic spectra. These complexes are proposed tohave extended Z-chloroterephthalato-bridged structure and to consist of two nickel(Ⅱ). The variable-temperature magnetic susceptibilities of complex 1 were measuredover 4. 2～300 K and the data were fitted by least-squares to a susceptibility equationderived from the Hamiltonian operator, giving the exchange integral ZJ=1. 6 cm-1, which indicate a very weak antiferromagnetic interaction between nickelf (Ⅱ) ions.

Automatic Web services composition algorithm based on optimal matching

A novel layered method was proposed to solve the problem of Web services composition.In this method,services composition problem was formally transformed into the optimal matching problem of every layer,then optimal matching problem was modeled based on the hypergraph theory,and solved by computing the minimal transversals of the hypergraph.Meanwhile,two optimization algorithms were designed to discard some useless states at the intermediary steps of the composition algorithm.The effectiveness of the composition method was tested by a set of experiments,in addition,an example regarding the travel services composition was also given.The experimental results show that this method not only can automatically generate composition tree whose leaf nodes correspond to services composition solutions,but also has better performance on execution time and solution quality by adopting two proposed optimization algorithms.

Study of the Mode of Cost-sharing by Indi-viduals for Higher Education in China

In recent years, financial crises of higher education have become universal. The policy of cost-sharing by in- dividuals was tried out in many countries. However, empirical studies have shown that the policy has, to a certain de- gree, negative effects for the poor in accepting higher education costs. This paper points out it is the mismatch between tuition fees and the ability to pay that causes the problem. Using two dimensions of group and time to pay, a mode sys- tem, including seven modes for the individual to share the cost of higher education, was constructed. It is suggested that only three modes of pay-immediately have been carried out in China and they all have same shortcomings. To try new modes and exercise different modes synthetically will be meaningful for solving the questions that exist in the current policy.

An 8GHz Internally Matched AlGaN/GaN HEMT Power Amplifier with RC Stability Network

8GHz 20W internally matched A1GaN/GaN HEMTs have been developed. The input and output matching net- works are realised with microstrip lines on a 0. 381mm thick alumina substrate. To improve the stability factor K of the device, a lossy RC network is used at the input of the device. The developed internally matched power amplifier module exhibits 43dBm （20W） power output with a 7.3dB linear gain,38.1% PAIE,and combined power efficiency of 70.6% at 8GHz.

Surgical anatomy of innervation of the gallbladder in humans and Suncus murinus with special reference to morphological understanding of gallstone formation after gastrectomy

AIM： To clarify the innervation of human gallbladder,with special reference to morphological understanding of gallstone formation after gastrectomy.METHODS： The liver, gallbladder and surrounding structures were immersed in a 10 mg/L solution of alizarin red S in ethanol to stain the peripheral nerves in cadavers （n = 10）. Innervation in the areas was completely dissected under a binocular microscope. Similarly,innervation in the same areas of 10 Suncus murinus （S. murinus） was examined employing whole mount immunohistochemistry.RESULTS： Innervation of the gallbladder occurred predominantly through two routes. One was from the anterior hepatic plexus, the innervation occurred along the cystic arteries and duct. Invariably this route passed through the hepatoduodenal ligament. The other route was from the posterior hepatic plexus, the innervation occurred along the cystic duct ventrally. This route also passed through the hepatoduodenal ligament dorsally.Similar results were obtained in S. murinus.CONCLUSION： The route from the anterior hepatic plexus via the cystic artery and/or duct is crucial for preserving gallbladder innervation. Lymph node dissection specifically in the hepatoduodenal ligament may affect the incidence of gallstones after gastrectomy.Furthermore, the route from the posterior hepatic plexus via the common bile duct and the cystic duct to the gallbladder should not be disregarded. Preservation of the plexus may attenuate the incidence of gallstone formation after gastrectomy.