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In order to realize the rational utilization of low-grade polymetallic symbiotic mineral resources with low input, typical copper–nickel symbiotic low-grade ores were used as the test object. After careful process mineralogy research on the ore, it was learned that the main valuable elements of the ore were Cu and Ni, and the content of these two elements was 0.16 wt.% and 0.39 wt.%, respectively. The main copper-bearing mineral in the ore was chalcopyrite, and the main nickel-bearing mineral was pentlandite Useful minerals were finely distributed in ores. Based on the properties of ore, a beneficiation process of one stage grinding copper/nickel mixed flotation copper/nickel separation was proposed. A copper concentrate with a Cu grade of 17.08 wt.% and a nickel concentrate with a Ni grade of 4.63 wt.% were obtained by separation. This study provides a lowinvestment technical solution for the rational utilization of polymetallic paragenetic mineral resources. [ABSTRACT FROM AUTHOR]

Chinese Sturgeon Natural Reserve (CSNR) is a typical river ecosystem in the middle of the Yangtze River. An evaluation system of the river ecosystem services of CSNR was established using the so-called 'Market Price Approach', 'Expense Payment Method', 'Contingent Valuation Method', 'Substituted Value Method', 'Cost Analysis Method' and 'Opportunity Cost Method'. The results showed that the total values of the ecosystem goods and services of the natural reserve amount to an estimated 73.57 million USD. The use-values and non use-values were 72.5 and 27.5%, respectively. The direct use values, including fisheries, water supplies and others, reach a total of about 24.23 million USD; On the other hand, the indirect use values, which include endangered species, purification costs and degradation losses, have been estimated at cost levels of approximately 29.12 million USD, indicating with 39.6% its important role of the total value. Meanwhile the non-use values of CSNR in the Yichang Reaches of the Yangtze River were assessed by a contingent valuation method (CVM) and the willingness to pay (WTP), The study shows that the annual non-use values of CSNR is up to 20.22 million USD, of which its existence values is in the range of 8.59 million USD, its bequest values 8.03 million USD, and the option values around 3.6 million USD. This preliminary analysis indicates that this natural reserve represents a special hydro-ecosystem in China with the sturgeon as target species, which is highly valued. The value of endangered aquatic species is up to 25.2% of the total, which places much emphasis on aquatic species. Investment in scientific research and management is presently quite low, amounting to only 0.7% of the total; this fact incidates that research work should be given more concern and support. Limited by the data availability, data processing capacity and time given, result of this initial investigation only represents part of CSNR's assessable value, however, considering the reality that lots of water resource and hydropower projects are now on the way, this valuation will still be helpful to inform the public with the importance of protecting endangered aquatic wildlife and such special hydro-ecosystem. [ABSTRACT FROM AUTHOR]

In this article we focus on the detection of possible outliers based on the widely used boxplot procedures. The outliers in a set of data are defined to be a subset of observations that appear to be inconsistent with the remaining observations. We identify the outliers by constructing a boxplot with its lower fence (LF) and upper fence (UF) either (a) satisfying the requirement that if the given sample is outlier-free, then the probability that one or more of the sample data would fall outside the region (LF, UF) is equal to a prescribed small value a, or (b) taken to be the tolerance limits, derived from an outlier-free random sample, within which a specified large proportion fi of the sampled population would be asserted to fall with a given large probability y. Exact expressions that can be routinely used to evaluate the constants needed in the construction of the boxplot's outlier region for samples taken from the family of location-scale distributions are obtained for both procedures. This article shows that the commonly constructed boxplot is in general inappropriate for detecting outliers in the normal and especially the exponential samples. We recommend that the graphical boxplot be constructed based on the knowledge of the underlying distribution of the dataset and by controlling the risk of labeling regular observations as outliers. [ABSTRACT FROM AUTHOR]

Shewhart mean and variance schemes continue to enjoy great popularity among process engineers because they are easy to understand and are the most sensitive in detecting large process shifts. For some processes, for example the screen printing process in memory modules assembly, there is a possibility of the process mean and variance shifting at the same time due to special causes. Thus, instead of studying the joint behavior by looking at the mean and variance information on two separate charts, it is practical and usually more meaningful to look at the combined mean and variance information on an interval charting scheme. The interval scheme is found to have a similar run length performance to the Shewhart mean and variance schemes and only a single chart needs to be managed. A simple design procedure for the interval scheme that matches the corresponding Shewhart scheme is provided for easy implementation. Also, the interval and Shewhart schemes are compared based on real manufacturing data sets. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A retrospective study was performed to evaluate breast imaging in the Wilford Hall Medical Center, the largest medical facility in the U.S. Air Force, from the time period of October 1997 to October 2000, in comparison with its civilian counterparts. The results demonstrate that although Wilford Hall Medical Center breast imaging is faced with unique difficulties in having a relatively mobile patient and physician population, military breast imaging corresponds with civilian breast imaging in the following aspects: screening the eligible population according to age and risk factors, cancer and precancerous abnormality detection rate, and biopsy techniques, including stereotactic-guided vacuum-assisted, automated gun biopsy, ultrasound-guided biopsy, and needle localization-assisted excision biopsy. Positive predictive value based on biopsy recommendations are lower than in civilian practice, likely because military radiologists are keenly aware of the mobile status of their population and are more aggressive in recommending biopsy for a definitive diagnosis rather than mammographic follow up. In our practice, cancer diagnosed at stage 0 or 1 is 85%, 4.3% of patients have positive lymph nodes, the overall cancer detection rate per 1,000 population is 3.97, the recall rate is 8.8%, sensitivity is 100%, and specificity is 98.1%. All of these aspects are comparable with those of civilian practice. [ABSTRACT FROM AUTHOR]

The cumulative sum (CUSUM) and exponentially weighted moving average (EWMA) charts are often recommended for process monitoring when a quick detection of small or moderate sustained shifts in the process mean is desired. In general, the moving average (MA) chart is slightly less sensitive than the EWMA or CUSUM chart in detecting the intended shift but the overall performance is quite similar. The in-control run length distributions of the MA chart and the corresponding EWMA chart are nearly identical. The MA chart is much simpler to understand because it is based on the simple average, and the MA is used widely in the financial sector for smoothing stock and index trends. We develop a simple design procedure for the MA chart and the combined MA-Shewhart scheme for an easy implementation. [ABSTRACT FROM AUTHOR]

AgInTeSbGe thin films were deposited by the de sputtering method, Due to germanium doping in the AgInTeSb film, new Ag2Te and Ge2Sb2Te5 crystalline phases were formed, The crystallization temperature and the activation energy of the AgInTeSbGe thin film increased manifestly with the addition of Ge. The refractive index n and the extinction coefficient k of the AgInTeSbGe film in the amorphous and crystalline states were measured. The reflectivity contrast of the AgInTeSbGe phase-change optical disk was greater than %30 in almost the whole visible region. A minimum recording mark of about 220 nm in length was recorded using the AgInTeSbGe thin film as the recording medium. The reflectivity contrast of the minimum recording mark was about %25. [ABSTRACT FROM AUTHOR]

Ab-initio calculations are carried out for the Er-related electrically active centers in Si. Our proposed microscopic model is consistent with photoluminescence measurements on Si:Er and Si:Er:O samples. For isolated Er, the tetrahedral interstitial site is the stable configuration, being related to the photoluminescence lines in Si:Er. Several configurations containing oxygen and fluorine atoms, surrounding the Er impurities, are proposed to simulate the effects of co-implantation. The results suggest that six oxygen atoms around substitutional Er can stabilize the center, which can be related to the strong photoluminescence lines in Si:Er:O samples. On the other hand, no configuration containing fluorine atoms could explain the stronger photoluminescence lines resulting from fluorine co-implantation. [ABSTRACT FROM AUTHOR]

A new heterocyclic push–pull azo compound-in-poly(methymethacrylate) (PMMA) film has been made by means of the spin-coating method. The spectroscopic properties of the films have been investigated with the steady-state absorption spectra, and steady-state fluorescence and femtosecond time-resolved fluorescence spectra in the first time, which is an important characteristic for the application of the film. The excited singlet (S1) state lifetimes for trans and cis isomers of the film at room temperature have been measured. The excited triplet (T1) state lifetime of cis isomer of the film has been obtained. The electronic structure of the film has been explained. The results show that the aggregate state of the azo molecules greatly influences its absorption spectra. [Copyright &y& Elsevier]

Presents information on a study which fabricated the thin-film transistor (TFT) with cadmium (Cd) selenium and Cd sulphur semiconductor thin films. Use of the chemical bath deposition method in the fabrication of TFT; Processes for TFT fabrication; Results and discussion.

The conventional Shewhart &Xmacr; chart is developed based on the assumption that the within-sample variation is due to the inherent process variation, and any significant variation between samples is attributed to the existence of assignable causes. In the manufacturing industry there are processes where there is variation between samples due to the inherent process variation. A straightforward application of the conventional Shewhart &Xmacr; chart would thus result in more frequent false alarms. The problems associated with various Shewhart &Xmacr; charts in monitoring such a process are discussed using a real data set from an integrated circuit (IC) assembly process. A Shewhart &Xmacr; chart with modified limits is adapted for such a process. In addition to the usual ability to signal for assignable causes, the &Xmacr; chart with modified limits is also developed as a tool to signal the need for adjustment of controllable process variables for improving the process capability. Practical application of this chart in monitoring an IC assembly process is discussed. Copyright © 1999 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A modified geometric model is proposed for fitting data generated from a process where most of the samples are conforming and occasional samples are non-conforming. These near-zero-defect processes are classified as processes subjected to random shocks. A graphical comparison of the goodness of fit of industrial process data using modified geometric and modified Poisson models is performed. The geometric model is found to provide a better fit than the Poisson model. Based on the modified geometric model, a charting scheme consisting of two charts is developed to monitor a process subjected to random shocks. A cumulative count of conforming chart is used to monitor the frequency of random shocks and a geometric chart is used to monitor the count of non-conformities. The geometric chart performs better than the Poisson chart in terms of false alarm rate. The performance of the scheme is also evaluated. Copyright © 1999 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we explore the major, minor and some trace elements of sixty-five glass beads from eighteen oasis sites both north and south of the Taklamakan Desert, the ancient centre of the Silk Routes linking East and West; the samples date from the Warring States period (475–2211 BCE) to the Tang Dynasty (618–907 CE). Using a high-resolution portable XRF spectrometer, with special attention to issues of surface weathering and sample preparation, we obtained quantitative chemical compositional data that, when combined with archaeological context and the technology of bead manufacture, provide the basis for an understanding of both changes in glass type over time, and possible source areas for the Xinjiang glasses. While glass beads at the early sites (1st c. BCE to 4th c. CE) were coming primarily from Kushan-controlled territories in northern India, Pakistan and Afghanistan, with a small contribution from central China, most of the later glass (4th–10th c. CE) is similar to that produced in the Sasanian Empire at such sites as Veh Ardashir in central Iraq. These changes most likely reflect changing cultural and economic conditions in the Silk Road towns. [Copyright &y& Elsevier]

To obtain qualified electroless Ni–P coating on W–Cu composite, the influences of three different activation processes, chemical activation, chemical activation and strike nickel plating, and anodic activation and strike nickel plating, on the adhesion of electroless Ni–P coating to W–Cu composite have been studied in this paper. The adhesion between the Ni–P coating and the W–Cu composite has been estimated by scratch, file and bend tests. The results indicate that the samples, pretreated by anodic activation and strike nickel plating, have the qualified adhesion. The samples that pretreated by chemical activation and chemical activation and strike nickel plating do not have the qualified adhesion. SEM shows that the surface morphology of Ni–P coating is smooth, no hemispherical clusters appeared and XRD indicates that it has an amorphous structure. [ABSTRACT FROM AUTHOR]

A total of 46 stratified glass eye beads in Hubei Provincial Museum, Wuhan, China were analyzed in situ by means of portable X-ray fluorescence and Raman spectrometers. These beads were excavated from the famous tomb of Marquis Yi of the Zeng State, which was dated back to the early Warring States Period (433 bc or little late), in Hubei Province. It is determined that most of these elegant glass beads belong to the typical soda-lime-silicate glasses with low contents of MgO and K2O. The colorants used within these beads are attributed to two types: antimony-based compound opacifiers/colorants and the transition metals in their oxidized state such as Co, Cu, and Fe ions. According to their characteristics of typology, chemical composition, and micro-crystals within samples, we classified them into three subtypes and evaluated the possible relations among them. In addition, through comparing with the similar contemporary samples unearthed from Xu Jialing Tomb (5th-4th century bc) in Henan Province, we discussed the provenance of these stratified glass eye beads and relative issues briefly. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A total of 33 ancient glass beads unearthed from the Kizil reservoir cemetery and Wanquan cemetery in Xinjiang are studied using Raman spectroscopy, scanning electron microscopy with energy-dispersive spectrometry ( SEM- EDS) and other methods. The detailed study of the glassy matrices, the crystalline inclusions and the microstructural heterogeneities for these glass beads has revealed some valuable information to help in the understanding of their possible manufacturing technology and provenance. At least two different types of glass were present in the two cemeteries. For the first time, antimony-based colourant/opacifier-for example, Pb2 Sb2 O7 or CaSb2 O6-was systematically identified in some beads of plant-ash type soda-lime glass dated to about 1000-500 bc. The limited number of potash glass beads from the Kizil reservoir cemetery, which were dated to about 500-300 bc, used tin oxide as an opacifier. The diverse resources of the soda-lime and potash glasses indicate the existence of a complex trade network between China and the West much earlier than the Western Han Dynasty. [ABSTRACT FROM AUTHOR]

In this communication, the pavement repair strategy for the Bangabadhu multipurpose bridge has been optimized. The former design of the repair strategy includes six parts of repairing cracks with epoxy adhesive, 1.4 mm thick carbon fiber reinforced polymer (carbon fiber reinforced polymer), 5 mm thick thermal insulation, 6-12 mm surface material non-shrink mortar grout, 5 mm thick waterproofing membrane, and 50 mm thick mastic asphalt. The optimized repair proposal includes five parts of repairing cracks with epoxy adhesive, 1.4 mm thick carbon fiber reinforced polymer, 4-10 mm thick epoxy resin motar grout, 5 mm thick epoxy asphalt waterproofing adhesive coat, and 50 mm thick stone mastic asphalt. In addition, the requirements for the materials selection and specific technology for the construction processes has also been provided. [ABSTRACT FROM AUTHOR]

Confocal Raman microspectroscopy and portable X-ray fluorescence spectroscopy were used nondestructively to characterise 18 intact jade artifacts from the Cemetery of the Ying State in Pingdingshan, Henan Province, China. These jade artifacts date from the early to the middle of the Western Zhou Period (the mid-11th to the mid-9th century BC). Thirteen jade artifacts made of tremolite and two jade artifacts made of actinolite were discriminated from each other by their hydroxyl stretching modes, and a malachite pendant, a muscovite dagger-axe, and a crystal pendant were also identified. Black graphite was analysed in three jade artifacts composed of tremolite, and the mineralization temperatures were estimated and compared. A red powder was found on the surface of all of the jade artifacts, and this was found to be cinnabar (HgS), which is thought to have been added to the tomb environments during burial ceremonies. The chemical compositions and the possible provenances of the jade artifacts are briefly discussed. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Thirty-seven glass beads excavated from the Han Dynasty tombs in Hepu county, Guangxi, China, were analyzed using a portable X-ray fluorescence (PXRF) spectrometer. Reference sample Corning glass D is used to check precision and accuracy of the equipment for major and minor components. The results of inductively coupled plasma atomic emission spectroscopy and PXRF are compared to evaluate the quality of equipment for trace elements. Combined with the contents of Al2O3 and CaO, a new criterion of subgroup division for potash glass based on the levels of trace elements (Rb and Sr) is proposed. The correlations of Rb and K, Rb and Al, and Sr and Ca are discussed. It is thought that saltpeter was the main flux used to produce potash glasses of different groups. The positive correlation between Rb and Al, and Rb and K indicates that potassium aluminosilicate minerals may be used as raw minerals for potash glasses of group II. The results indicate that the levels of Rb and Sr can be very helpful in subgroup definition and provide useful clues to the raw materials used for glassmaking and provenance study of the potash glass found in Guangxi, China. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Comparing values of trace elements determined by external-beam proton-induced X-ray emission (PIXE) and inductively coupled plasma atomic emission spectrometry (ICP-AES) is important to find the provenience of raw materials of ancient nephrite artifacts, because most previous elemental characterizations of nephrite minerals were obtained by ICP-AES, but PIXE presents the possibility of nondestructive analysis for largely and integrally ancient nephrite artifacts. In this work based on 12 nephrite minerals, it shows that the distribution of trace elements of nephrite samples both in PIXE and ICP-AES data are generally consistent, although large differences exist in some elements. According to the trace elements, the two types of nephrite mineralization origins can be distinguished, determined by PIXE and ICP-AES, respectively. Moreover, depending on the PIXE and ICP-AES data, Sr can be regarded as fingerprint element of Xiaomeiling nephrite minerals, and the differentiation of Sr content between Xiaomeiling nephrite minerals and ancient nephrite artifacts from Liangzhu culture (3300-2300 bc) is clear evidence that the raw materials of the artifacts are not from Xiaomeiling deposit. The nephrite minerals from Wenchuan deposit can be distinguished from other samples because of their high values of Mn/Fe. Therefore, the PIXE can be used with ICP-AES to judge mineralization mechanism and find fingerprint elements of raw materials of ancient nephrite artifacts. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

FePt thin films are deposited on SrTiO3, MgO, and a 2 nm-FeOx underlayer on an Si substrate at room temperature and then annealed at elevated temperatures. Studies of the L10 ordering process in each case show that the ordering temperature for the FePt film on the nonepitaxial Si/FeOx, substrate is ∼150 °C lower than the epitaxial FePt films deposited on MgO and SrTiO3 substrates. We argue that internal stresses arising from lattice defects and a recrystallizing process as well as thermal strain from differences in thermal expansion between substrate and film are responsible for the differences in ordering kinetics from the A1 to L10 phase of FePt on the various substrates. [ABSTRACT FROM AUTHOR]

Thin films of four nickel(II) and copper(II) hydrazone complexes, which will hopefully be used as recording layers for the next-generation of high-density recordable disks, were prepared by using the spin-coating method. Absorption spectra of the thin films on K9 optical glass substrates in the 300–700 nm wavelength region were measured. Optical constants (complex refractive indices N) and thickness d of the thin films prepared on single-crystal silicon substrates in the 275–675 nm wavelength region were investigated on a rotating analyzer-polarizer scanning ellipsometer by fitting the measured ellipsometric angles (Ψ(λ) and Δ(λ)) with a 3-layer model (Si/dye film/air). The dielectric functions ε and absorption coefficients α as a function of the wavelength were then calculated. Additionally, a design to achieve high reflectivity and optimum dye film thickness with an appropriate reflective layer was performed with the Film Wizard software using a multilayered model (PC substrate/reflective layer/dye film/air) at 405 nm wavelength. [ABSTRACT FROM AUTHOR]

We quantitatively analysed the factors contributing to the optical transmission enhancement of a sub-wavelength Sb thin film lens, using the finite-difference time-domain (FDTD) method. The results show that the transmission enhancement of the dielectric with a Gaussian distributed refractive index loaded in a sub-wavelength circular hole is not only due to the high refractive index dielectric, but also due to the specific distributions of refractive index. It is the first study about the effects of the refractive index distribution on the transmission of a sub-wavelength aperture. This kind of lens has practical applications in the very small aperture lasers and for near-field optical storage and lithography. [ABSTRACT FROM AUTHOR]

The single-layer and multilayer Sb-rich AgInSbTe films were irradiated by a single femtosecond laser pulse with the duration of 120 fs. The morphological feature resulting from the laser irradiation have been investigated by scanning electron microscopy and atom force microscopy. For the single-layer film, the center of the irradiated spot is a dark depression and the border is a bright protrusion; however, for the multilayer film, the center morphology changes from a depression to a protrusion as the energy increases. The crystallization threshold fluence of the single-layer and the multilayer films is 46.36 mJ/cm2, 63.74 mJ/cm2, respectively. [ABSTRACT FROM AUTHOR]

External-beam PIXE was used for the non-destructive analysis of early glasses unearthed from the tombs of Warring States (475-221BC) and Han Dynasty (BC206-AD220) in south China. It was found that these glasses were basically attributed to PbO-BaO-SiO2 system and K2O-SiO2 system. The results from the cluster analysis showed that some glasses had exactly the same recipe. The source of the K2O flux and the correlation between PbO and BaO are discussed. Some archeological information is revealed. [ABSTRACT FROM AUTHOR]

Optical quality SrxBa1−xNb2O6 (SBN) thin films doped with Pr3+ ions were successfully grown on fused quartz substrates using a pulsed laser deposition technique. Both as-grown and annealed samples were studied at either room temperature or at 10 K. Luminescence measurements show that most 4f2→4f2 emissions from Pr3+ centers were efficiently quenched in the films. Strong red emission from 1D2 to 3H4 at ∼610 nm accompanied by weak emission to other 3Hj multiplets could be observed only by UV excitation into the SBN conduction band. At 10 K, the main emission peak splits into four components. In addition, a broadband SBN-host luminescence was identified at ∼560 nm in the annealed sample, associated with the charge-transfer vibronic exciton. As an interstitial ion, Pr3+ may occupy a 15-, 12-, 9- or 6-fold cage surrounded by oxygen and was found to occupy all four possible sites in SBN thin films. This behavior is different from Eu3+- SBN where Eu3+ only occupies a 6-fold site. [Copyright &y& Elsevier]

The titanium-doped Ge2Sb2Te5 films were deposited on Si(100) substrates by comagnetron sputtering method. The titanium concentrations in those films were determined by x-ray photoelectron spectroscopy. The influence of Ti doping upon phase change characteristics of the samples has been investigated by x-ray diffraction and a temperature-regulable UVISEL™ typed spectroscopic ellipsometry. With the augmentation of Ti doping concentration, the crystalline temperatures of the films went up while annealing, and the face-centered-cubic phase of them had high thermal stability because of the bond making between Ti and Te elements partly. [ABSTRACT FROM AUTHOR]

Tetragonal L10 FePt films are deposited on the pyramid-type Si substrates fabricated by chemical etching process from (100) Si wafers. The films are composed of different easy-axis orientation FePt grains, most of which with the easy axis along substrate normal, the others with the easy axis tilted from the normal direction. When the magnetic field is applied along the perpendicular direction, the easy-axis tilted grains reverse first, and then the magnetization reversal of the whole film is promoted. Small coercivity, suitable α, and high squareness are obtained. And the coercivity increases when the applied field is tilted from the normal direction. [ABSTRACT FROM AUTHOR]

The nonlinear optical properties of C[SUB60][NH[SUB2]- (CH[SUB2])[SUB3] -Si(OC[SUB2]H[SUB5])[SUB3]][SUB3] sol and gel were investigated by femtosecond optical Kerr gate technique at 820 nm. The nonresonant third-order optical susceptibilities were measured to be 1.4×10[SUP-13] and 1.6×10[SUP-13] esu for the C[SUB60][NH[SUB2]- (CH[SUB2])[SUB3]- Si(OC[SUB2]H[SUB5])[SUB3] sol and gel, respectively, which are two orders larger than that of C[SUB60] molecule. [ABSTRACT FROM AUTHOR]