Thermodynamic data from diffusion couples—II

A non-linear least squares based algorithm which permits one to estimate the activity composition relationship from the interdiffusivity data was applied to nine isomorphous binary alloy systems: CuAu, PdCu, CuNi, PdNi, AgAu, PdFe, AuNi, PtNi, and NbTi. The algorithm factors the interdiffusion coefficient into two terms: a thermodynamic term and another term representing the phenomenological coefficients. The problem is non unique hence; the algorithm leads to multiple solutions, one of which represents the thermodynamics of the systems whereas the others are spurious solutions. One additional piece of information such as the activity at one particular composition or the Henry's law constant at infinite dilution is needed to select the correct solution from the set of solutions. For eight of the ten binary systems the algorithm computed a possible solution that was close to the experimentally measured activity-composition curves confirming that it is possible to estimate activities from diffusion data. For the NbTi system the model provided fresh insight into its thermodynamics by suggesting the presence of a low temperature miscibility gap. The model may also be applied to system exhibiting a miscibility gap.     

Thermodynamic data from diffusion couples—I

A non linear least squares based method is presented to estimate activity data from measured interdiffusivity data for isomorphous binary metals. The interdiffusion coefficient is modelled as a product of two functions, one representing the thermodynamic contributions and another the contribution of the phenomenological coefficients. The proposed method factors the interdiffusion coefficient into its two constituent functions. This leads to the existence of non unique solutions and hence yields a set of possible solutions which on an activity-composition diagram exhibit positive and negative deviations from ideality. One additional piece of information, such as the experimentally measured activity at a particular composition or the slope of the Henry's law line at infinite dilution, is needed to select the correct solution. The method successfully predicted the thermodynamics of the CoNi system from calculations bases on the interdiffusion coefficient.     

Domestic Aluminum Plants Suffer from High Electricity Rates

A recent survey shows that 99% of China'saluminum plants are using electricity that ispriced higher than the international break-evenpoint for aluminum producers.     

Will it benefit from the WTO entry?.

On November 15,1999,after 13 years ofnegotiations between China and the UnitedStates,the two countries finally signedthe bilateral agreement on the issue ofChina's joining in the World Trade Organi-zation(WTO).This event marks an impor-tant step forward for China in its sus-tained efforts to become a member of theWTO,and with ongoing talks with the re-maining countries,China expects to fulfillthe joining procedures required by the     

Separation and Recovery of Phosphorus from P-bear-ing Steelmaking Slag

In order to recycle the phosphorus from P-bearing steelmaking slag, the influences of magnetic field inten- sities, slag particle sizes and slag compositions were investigated by magnetic separation experiments. SiO2, A1203 and TiO2 melting modification of converter slag was made respectively and phosphorus-rich phase was extracted by magnetic separation. The results show that MgO, MnO, Na2 0 and CaF2 have little effect on the phosphorus recovery, whereas the addition of SiO2, Al2 03, and TiO2 has great effect on phosphorus enrichment in slag and magnetic separation. With adding the reagent of SiO2 Al2 03 and TiO2, recycled non-magnetic substances are increased obviously and P2 05 content in nowmagnetic substances and phosphorus recovery rate are also increased. The phosphorus recovery rates of modified slag No. 8 （SiO2 modification）, slag No. 10 （AI2 03 modification） and slag No. 11 （TiO2 modification） are 84.75 %, 82.16 % and 74.46 %, respectively. Then, most of phosphorus was recycled.     

Energy Transfer from PVK to Europium Complex in Electroluminescence

The spectra of solutions, films and light-emitting diodes of rare earth complexes were studied. It is shown that the absorption spectra of PVK-dopping rare earth complexes can be red-shifted to the visible region and overlap with the emission spectrum of PVK, which makes the energy transfer possible from PVK to the rare earth ion.     

Preliminary Study on Partially Metamict Allanite from Guposhan Granites

ＰｒｅｌｉｍｉｎａｒｙＳｔｕｄｙｏｎＰａｒｔｉａｌｌｙＭｅｔａｍｉｃｔＡｌｌａｎｉｔｅｆｒｏｍＧｕｐｏｓｈａｎＧｒａｎｉｔｅｓＹａｎｇＸｕｅ－Ｍｉｎｇ；（杨学明）（ＤｅｐａｒｔｍｅｎｔｏｆＥａｒｔｈａｎｄＳｐａｃｅＳｃｉｅｎｃｅｓ，Ｕｎｉｖｅｒｓｉｔ...     

Radiation emission from the ＂Rhodotron-TT200＂ cavity

In this paper, the X-rays emitted from the Rhodotron-TT200 cavity have been studied in depth. We found that the Bremsstrahlung interaction is the only contribution of X-ray generation important to safety. The X-ray dose rate in the Rhodotron vault is calc     

Industry association takes over some administrative functions from State Bureau

According to a circular issued by the StateNonferrous Metals Industry Administration(SNMIAI,some of its administrative func-tions will be passed on to the newly es-tablished China Nonferrous Metals IndustryAssociation ICNMIA).     

Blue-Light Emission from Undoped and Rare Earth-Doped Wide Bandgap Oxides

Blue-light emitting materials have been receivingconsiderable attention due to their applications for avariety of optoelectronic devices and display technolo-gies . Rare earth-doped compounds have long founduses as blue phosphors in a variety of devices due totheir intensely luminescent f-d and f-f electronictransitions[1]. Metal sulfides ,such as ZnS have beenutilized as conventional phosphors due to their excel-lent brightness . However ,the life span of the displaydevices is li mited due t…     

Preschoolers infer ownership from “control of permission”.

Owners control permission—they forbid and permit others to use their property. So it is reasonable to assume that someone controlling permission over an object is its owner. The authors tested whether preschoolers infer ownership in this way. In the first experiment, 4- and 5-year-olds, but not 3-year-olds, chose as owner of an object a character who granted or denied another character permission to use it. In Experiment 2, older 3-year-olds chose as owner of an object a character who prevented another character from using it when prevention was accomplished by controlling permission but not otherwise. Younger 3-year-olds chose between the characters at chance. These findings indicate that preschoolers infer ownership from control of permission. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Enhanced Copper Removal from Activated Sludge Using Bioferric∕Selectors

Effluent copper concentrations from a pilot-scale conventional activated-sludge system (control) were compared with those from a conventional pilot treatment process that also integrated bioferric∕selector units. The bioferric∕selector units employed iron coagulation within the activated-sludge basin and also provided storage of activated sludge in a nonaerated selector for a period of 18–24 h. During pseudo-steady-state operation over a 30-day period, the systems employing the bioferric∕selector treatment consistently yielded lower effluent copper concentrations than did the controls. Although influent copper concentration ranged from 126 to 723 ppb (228 ppb average), the two bioferric∕selector units achieved an average effluent copper concentration of 22 ppb, whereas the two conventional controls achieved an average of 40 ppb. The difference in copper concentrations between the bioferric∕selector units and the controls was statistically significant to the 99.5% confidence level when comparing effluent copper concentrations as a function of mixed-liquor volatile suspended solids (MLVSS). For both conditions, lower effluent copper corresponded to higher MLVSS, and for equal levels of MLVSS, the bioferric∕selector units statistically achieved lower effluent copper concentrations than did the controls. Likewise, Freundlich isotherm plots indicated that the MLVSS (or MLSS) that had undergone the bioferric∕selector treatment achieved statistically greater capture of copper than did their control counterparts.     

Are performance appraisal ratings from different rating sources comparable?

The purpose of this study was to test whether a multisource performance appraisal instrument exhibited measurement invariance across different groups of raters. Multiple-groups confirmatory factor analysis as well as item response theory (IRT) techniques were used to test for invariance of the rating instrument across self, peer, supervisor, and subordinate raters. The results of the confirmatory factor analysis indicated that the rating instrument was invariant across these rater groups. The IRT analysis yielded some evidence of differential item and test functioning, but it was limited to the effects of just 3 items and was trivial in magnitude. Taken together, the results suggest that the rating instrument could be regarded as invariant across the rater groups, thus supporting the practice of directly comparing their ratings. Implications for research and practice are discussed, as well as for understanding the meaning of between-source rating discrepancies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

NarL dimerization? Suggestive evidence from a new crystal form

The structure of the Escherichia coli response regulator NarL has been solved in a new, monoclinic space group, and compared with the earlier orthorhombic crystal structure. Because the monoclinic crystal has two independent NarL molecules per asymmetric unit, we now have three completely independent snapshots of the NarL molecule: two from the monoclinic form and one from the orthorhombic. Comparison of these three structures shows the following: (a) The pairing of N and C domains of the NarL molecule proposed from the earlier analysis is in fact correct, although the polypeptide chain connecting domains was, and remains, disordered and not completely visible. The new structure exhibits identical relative orientation of N and C domains, and supplies some of the missing residues, leaving a gap of only seven amino acids. (b) Examination of corresponding features in the three independent NarL molecules shows that deformations in structure produced by crystal packing are negligible. (c) The "telephone receiver" model of NarL activation is confirmed. The N domain of NarL blocks the binding of DNA to the C domain that would be expected from the helix-turn-helix structure of the C domain. Hence, binding can only occur after significant displacement of N and C domains. (d) NarL monomers have a strong tendency toward dimerization involving contacts between helixes alpha 1 in the two monomers, and this may have mechanistic significance in DNA binding. Analogous involvement of helix alpha 1 in intermolecular contacts is also found in UhpA and in the CheY/CheZ complex.     

Standards set for separation of large enterprises from government institutions

According to a report from the China Ma-terials News,China's enterprises separatedfrom the direct management of govern-ment institutions should belong to the 120enterprises groups and the 512 large pro-duction units with over 500 million yuan(US60.46 million)of asset and the equal     

China''''s import tax adjustments of some metals starting from 2001

争┌─────────────────────────────────┬──────┬──────┐│Nsme of CommoditieS │P丫evious加x│New加x rates││ │ rates │ │├─────────────────────────────────┼──────┼──────┤│CoPPer(Items under the Customs tax regulations ChaPter 74) │ │ │├─────────────────────────────────┼──────┼──────┤│Unwrou只ht eoPPer zine alloV(brass) │4 │2.5 │├───…     

Exports of China's Maior Nonferrous Metals from 1981 to 1994

5metals Produetion inereased.China be-eame one of the main nonferrous metalsProdueing and trading eountries in theworld.The total value of nonferrous metalsforeign trade,incl uding imPorts andexPorts over the Period were USD 13.947 billion,of which exPorts were USD4 .523 billion,imPorts 9.424 billion.EXPORTS一一一aluminium andalloy388,500 tonnes;lead and alloy 426,100tonnes:zinc and alloy 591,500 tonnes:tin and alloy 141,200 tonnes二refinedantimony 108,500 tonnes.over this Period,the v…     

What do people want from dentistry? An action research approach

Issues surrounding access to dentistry will be presented from information gathered during an action research project targeting three population groups. This project was conducted by students in the Dental Hygiene Degree Completion Program at the University of British Columbia and by the dental hygiene diploma students at Camosun College. In contrast to typical empirical dental studies which are validated by statistical presentation, action research uses an interview process and qualitative analysis to identify what people really think, believe and do. College students, independent-living seniors, and low-income families were interviewed to determine how they accessed dental care, how they liked their dental visits, and how they preferred to receive dental health information. Cost, convenience and fear of pain were significant factors which influenced whether people attended the dental office. Caring dental health providers, comfort and pleasant physical surroundings were important features of a dental office visit. Dental health practices, such as brushing and flossing, were predominantly learned from the dental profession at the dental office, through school programs, or from parents at home. This data challenged our previous assumptions about these groups. As the goal of this type of research is "action", the information gathered will lead to action plans at the community and professional level.     

Copper Demand from China’s Wire and Cable Industry-Part I

<正>1. Reality of China’s wire and cable industry China, with a total wire and cable industry output value in excess of the United States, has