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Renewable energy markets have recently emerged in countries participating in the Belt and Road Initiative (BRI). Despite having abundant renewable energy resources, these countries contribute only a small share of global renewable energy investment. This study examines the nexus between governance, renewable energy investment, and trade openness for a sample of 51 BRI countries from 1996 to 2017. Specifically, the gravity model of trade is used to develop an instrumental variable for trade openness. The empirical findings reveal that political stability, the rule of law, regulatory quality, and corruption control are statistically significant factors that influence renewable energy investments in BRI countries. Moreover, this relationship seems to depend on the degree of trade openness. Our results are robust to various econometric specifications.

Reverse flotation was used to recover metal components from waste printed circuit boards (PCBs). The micro-morphology and chemical composition analysis of raw materials indicated that waste PCBs are mainly composed of glass fibers, ceramics and valuable metals. The effects of collector dosage and temperature on flotation efficiency were investigated and evaluated. The flotation results using various collectors showed that the efficient recovery of metal components could be achieved via reverse flotation with the diesel oil (DO) dosage of 370–1110 g/t, composite collector (CC) dosage of 370–740 g/t and laurylamine (LAM) dosage of 740 g/t, respectively. The suitable temperature should be controlled at around 20 °C for these collectors. The results also indicated that the selectivity of DO for nonmetal particles was stronger than that of CC and LAM. In summary, reverse flotation is a feasible and environmental approach for disposal of waste PCBs.

Extrusion dripping is a facile method for the preparation of millimetre-size macrobeads. In this work, a pneumatic extrusion dripping system has been established to fabricate hydroxyapatite macrobeads with a controlled size. The size of the hydroxyapatite spherical beads could be tailored by adjusting the dripping parameters. This work is believed to provide an alternative method for the fabrication of hydroxyapatite macrobeads that can be used in bone regeneration.

Porous fibers had better performance in many application fields for their larger surface area or extra nano topography than smooth ones. However, high vapor pressure solvents or selective removal of one phase from fastidious blended fibers were mostly used to fabricate porous fibers in electrospinning process, which made the process unfriendly and inconveniently. Here, a facial process on fabrication of porous fibers was developed by integrating the principles of thermally induced phase separation with the self-made cryogenic electrospinning system (CES) which can provisional solidify the polymer jet on the freezing collector. For demonstration, the polymer solution of Polycaprolactone (PCL) with solvent of glacial acetic acid was chosen. The PCL porous fibers with diameter of 3.29 ± 0.42 μm were successfully prepared at the height of 90 mm and freezing temperature of −3.6 ± 0.3℃ on collector in room environment. Furthermore, the pores on the surface of fibers exhibited two types: pits and polygon concaves. The pits were induced by phase separation at freezing temperature and the polygon concaves were due to the interaction of residual solvent with ice crystals on surface of silicon wafer or metal collector recruited from the air moisture. Generally, this process was suitable to polymer solutions with solvents of low vapor pressure but high freezing point.

A first time report on a solid-state polymorphic transformation of MOF materials [Zn2(bdc)2(dabco)]n (ZnBD) and [Co2(bdc)2(dabco)]n (CoBD) from a pillared kagome-lattice form (ZnBDkgm or CoBDkgm) to a pillared square-lattice form (ZnBDsql or CoBDsql) at ambient condition is given. Several solvents were applied as a guest-driven molecule to trigger the solid-to-solid transformation while only methanol demonstrated to be able to perform this transformation. The methanol-driven solid-state transformation behavior was observed by using powder X-ray diffraction. The morphology investigated that the rod-like Kagome form rapidly transformed into a tubular square lattice upon addition of methanol at room temperature. The characteristic porosity reconfirmed the transformation was complete. A transformation mechanism of disconnection-deformation-rebuilding was elucidated based on the experiment.

Long non-coding RNAs (lncRNAs) can be used as prognostic biomarkers in many types of cancer.We sought to establish an lncRNA signature to improve postoperative risk stratification for patients with localized clear cell renal cell carcinoma (ccRCC).Based on the RNA-seq data of 444 stage I-III ccRCC tumours from The Cancer Genome Atlas project, we built a four-lncRNA-based classifier using the least absolute shrinkage and selection operation (LASSO) Cox regression model in 222 randomly selected samples (training set) and validated the classifier in the remaining 222 samples (internal validation set). We confirmed this classifier in an external validation set of 88 patients with stage I-III ccRCC from a Japan cohort and using quantitative reverse transcription polymerase chain reaction (RT-PCR) in another three independent sets that included 1869 patients from China with stage I-III ccRCC.Univariable and multivariable Cox regression, Harrell's concordance index (c-index), and time-dependent receiver operating characteristic curves were used to evaluate the association of the classifier with overall survival, disease-specific survival, and disease-free survival.Using the LASSO Cox regression model, we built a classifier named RCClnc4 based on four lncRNAs: ENSG00000255774, ENSG00000248323, ENSG00000260911, and ENSG00000231666. In the RNA-seq and RT-PCR data sets, the RCClnc4 signature significantly stratified patients into high-risk versus low-risk groups in terms of clinical outcome across and within subpopulations and remained as an independent prognostic factor in multivariate analyses (hazard ratio range, 1.34 [95% confidence interval {CI}: 1.03-1.75; p=0.028] to 1.89 [95% CI, 1.55-2.31; p0.001]) after adjusting for clinical and pathologic factors. The RCClnc4 signature achieved a higher accuracy (mean c-index, 0.72) than clinical staging systems such as TNM (mean c-index, 0.62) and the stage, size, grade, and necrosis (SSIGN) score (mean c-index, 0.64), currently reported prognostic signatures and biomarkers for the estimation of survival. When integrated with clinical characteristics, the composite clinical and lncRNA signature showed improved prognostic accuracy in all data sets (TNM + RCClnc4 mean c-index, 0.75; SSIGN + RCClnc4 score mean c-index, 0.75). The RCClnc4 classifier was able to identify a clinically significant number of both high-risk stage I and low-risk stage II-III patients.The RCClnc4 classifier is a promising and potential prognostic tool in predicting the survival of patients with stage I-III ccRCC. Combining the lncRNA classifier with clinical and pathological parameters allows for accurate risk assessment in guiding clinical management.The RCClnc4 classifier could facilitate patient management and treatment decisions.

© 2018 Elsevier B.V. Poly (lactic acid) (PLA) is extensively used as an eco-friendly compound for many applications. The synthesis of stereo-pure lactide, specifically L,L-lactide which is the most desired isomer for the synthesis of high-quality PLA is very important. In this work, various materials including MOFs and simple bases have been applied as catalysts for the Lactide synthesis. Herein we report the one-step synthesis of L,L-lactide with high selectivity and yield (99%) in the absence of racemization by applying a cost-effective Cs2CO3 catalyst. The novel described procedure is even expected to be very efficient for industrial applications. ispartof: Catalysis Communications vol:114 pages:33-36 status: published

Tobacco bacterial wilt (TBW) and tobacco black shank (TBS) are two of the most devastating tobacco soil-borne diseases worldwide. In this study, Pseudomonas aeruginosa NXHG29 exhibited dually antagonistic activities against TBW and TBS in vitro assays. Pot experiments were performed to evaluate the capability of a novel bio-organic fertilizer (BOF) consisting of organic fertilizer with NXHG29 to control TBW and TBS. The results showed that application of BOF could more effectively decrease the disease incidence of TBW and TBS than the direct application of NXHG29. Higher amounts of BOF application (0.5% and 1% amendment) resulted in the more suppressive effects on tested pathogens when compared with a low amount of BOF application (0.1% amendment). To determine the antagonistic mechanism of NXHG29, we investigated the colonization pattern of NXHG29 on tobacco roots in a sand system and a natural soil system by tagging NXHG29 with a GFP-marked plasmid. Similar observations were obtained in the two systems. The results indicated that GFP-tagged NXHG29 colonized first the differentiation zones followed by the elongation and maturation zones of the primary roots and subsequently around the junctions of primary and lateral roots. The population dynamics of GFP-tagged NXHG29 on tobacco roots and in the rhizosphere were also monitored. The development of the BOF using dually antagonistic bacteria might provide new options for control strategies, especially with respect to managing both diseases simultaneously in the host plant, which should be more effective in the long term.

The die roll of fine-blanking parts is an important indicator when evaluating quality of parts. In this paper, the formation of die roll during the punching process is analyzed through the difference of the velocity of material between the die roll area and center area. At first, an assumption is made that every die roll is determined by the volume proportion of the part and waste area in the circular affected zone, and it is proved by simulation. In addition, the introduction of insertion block can prevent the fracture on the shearing surface without V-ring. In consideration of waste affect area and insertion block, a novel combined method is designed to decrease the die roll. It turns out that the height of die roll can be reduced by as much as 70% in both FEM simulation and actual experiment, which shows a great potential in fine-blanking industry.

Metal–organic polyhedra (MOPs) have attracted great interest in the past decade. As a new series of nano-material, MOPs have high outer and inner specific surface areas and are able to be applied in different areas such as catalysis, gas sequestration, drug delivery, molecule sensing, etc. In this review, the focus is made on the design and synthetic strategies approaching edge-bridged tetrahedra MnL6 and face-capped tetrahedra MnL4. Besides the synthesis, structure, and properties of tetrahedral self-assemblies are also considered, while tetrahedra will be compared with other complicated multinuclear constructions. The discussion of how the properties of tetrahedral cages can be altered by varying employed subcomponents is made. Moreover, the multifarious host–guest system and behavior of metal–organic tetrahedral self-assemblies for catalytic applications are addressed in details.

A 2 × 4 -cell superconducting linac module for the THz-FEL facility has been developed at the China Academy of Engineering Physics, which is expected to provide 6–8 MeV quasi-CW electron beams with an average current of 1–5 mA. The module consists of two 4-cell SRF cavities, two main couplers, two tuners and a cryostat. The design, fabrication and performance test of these components is presented in this paper. The test results reveal that all these components have reached their design goals and the module has also been assembled and horizontal tested at Chengdu. The gradients of both cavities at 2 K reach 10 MV/m, which meets our requirements. Currently beam-loading commissioning is underway.

Biogas is a renewable fuel source of methane that can be used as energy for vehicles after a purification process to remove impurities (Biogas upgrading and cleaning). However, removal of CO2 from methane is one of the critical steps for biogas upgrading and is limiting its commercial application. An overview of the materials in technologies of separation (membrane) and sorption (sorbents) know-how, including chemisorbents and physisorbents, has been made with a particular emphasis on biogas upgrading. The alternative properties and possibilities of different technologies and materials for CO2 separation, including alkanol amine, solid alkanol amine, zeolites, carbonaceous, metal-organic frameworks (MOFs), zeolitic imidazolate frameworks (ZIFs), and membrane applied for purifying raw biogas (upgrading) to produce bio-methane and on the other hand, to reduce CO2 emission from fossil fuel are discussed in this review.

The defect formation in metal–organic frameworks (MOFs) initiated by the crystal growth-rate of different synthesis procedures affects the structure, morphology and other properties of MOFs such as particle shape, gas adsorption capacity and specifically catalytic performance etc. Although the design of defect structures and the defect structures itself are well known, comparatively little is known regarding defect creation introduced by the synthesis procedure (different from mixed-linker approach, the use of acid modulators, post-synthetic treatment, etc.) and characterization of the resulting naturally occurring abnormalities (defects) in the material. Moreover, high performance of MOFs in various catalytic reactions can be correlated to the higher amount of defect structures because defects can possibly exhibit acid and/or basic properties. While studies of MOF crystallinity confirmed that for a given type of MOF different synthesis methods generate samples of similar crystal structures, their morphologies are often different due to the differences in the crystallization rates associated with these methods.

A series of metal organic frameworks (MOFs) MDABCO (M = Co, Ni, Cu, Zn; DABCO = 1,4-diazabicyclo[2.2.2]octane) are utilized as catalysts for the bulk ring-opening polymerization of l -lactide. The catalytic activity varies in the order CuDABCO, NiDABCO

A direct synthesis of pillared metal-organic frameworks with Kagome net topology under mild conditions (room temperature and ambient pressure) was developed which provides a straightforward and energy-saving procedure to produce MOFs. A series of metals (M = Zn, Ni and Co) bridging with ligands 1,4-benzene dicarboxylate (bdc) and 1,4-diazabicyclo[2.2.2]octane (dabco) were used to construct MOF frameworks denoted as M 2 (bdc) 2 (dabco). The Kagome net pillared structures were confirmed via crystal phase analysis (XRD). The use of different metals resulted in diverse crystal morphologies and particle shapes as observed from scanning electron microscope analysis (SEM). The obtained Kagome net pillared structure influences the physical properties such as surface area, pore size, N 2 /CO 2 /CH 4 gas adsorption and also thermal stability. Furthermore, modeling was applied to determine the behavior of the isosteric heat of adsorption on CO 2 and gas selectivity of CO 2 /CH 4 and CO 2 /N 2 .

A green, simple and low cost process for production of well dispersed, small size silver nanoparticles with narrow distribution from 3 nm to 15 nm was described. In this method, silver nanoparticles were prepared in aqueous medium by employing wolfberry fruit extract as both reducing and stabilizing agent without utilizing any other capping and reducing agent. The generation of metallic nanoparticles was observed by change of color and the UV–vis absorption spectroscopy. The obtained silver nanoparticles were analyzed by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The results show that the as-synthesized silver nanoparticles are highly crystalline in nature, spherical in shape. The reaction times, silver nitrate concentrations and wolfberry fruit extract amounts play crucial roles in the synthesis of small silver nanoparticles. The method displayed in this paper offers a very hopeful mean to prepare other noble nanoparticles using renewable materials as reducing and capping agent.

To improve the biological performance of hydroxyapatite scaffolds in bone tissue engineering, graphite was used as porogen to create additional micro/nanoporosity to macroporosity, resulting in hierarchical porosity. For maximum imitation of natural bone structures, scaffolds with different porosity features were fabricated using micron/nano-sized graphite. The sintering profile of graphite treated scaffolds was optimised to reduce the influence of shrinkage. To confirm the porosity features, the micro/nanostructures of scaffolds were characterised by scanning electron microscopy and Brunauer-Emmett-Teller method. Considering that hydroxyapatite is resistant to biodegradation in vivo, the degradation rate of scaffolds in modified simulated body fluid was examined. Furthermore, biological evaluations based on myoblasts were carried out to investigate the influence of porosity features on the essential performance such as adhesion, proliferation and differentiation. The results indicate that the scaffolds with dominant microporosity and little nanoporosity formed inside had high potential for clinical applications due to improved performance in bioactivity.

Structural color with polarization sensitivity has been widely studied due to its benefits for improving information storage and dynamic color display capacity. However, large amount and good concealment of information encoding are the major issues to be addressed. Here, we propose the elliptical Al/a-Si/Al (metal-insulator-metal, MIM) nanostructure arrays as the basic building blocks to realize polarization-sensitive subtractive structural colors for information encoding, and dynamic polarization-resolved displays. The experimentally realized structural color exhibits a wide color gamut covering the whole cyan, magenta, and yellow (CMY) color system, and presents a strong dependence on the incident polarization state due to its shape anisotropy. A new approach to improve the information encoding capacity is demonstrated using this structure combined with the polarization-independent nanostructures, increasing the concealment of information. Additionally, the polarization controllable dynamic display is engineered by the well-designed pixels with respect to different polarizations, generating the animation effect. These intrinsic properties and functionalities of the proposed structural color significantly extend its potential to the fields of information encoding, security encryption, and dynamic displays, not limited to color printing and filtering devices.

The recycling of waste printed circuit boards (PCBs) has been an emerging problem due to its hazardous nature. In this work, the flotation performances of metallic elements were investigated and evaluated at various temperature and collector dosage. The content of metals in flotation products was measured by the X-ray fluorescence spectrometer. When using 740 g/t diesel oil (DO) as the collector at 20 °C, recovery efficiency of Cu, Al, Zn and Ag reached the maximum values of 91.06%, 82.50%, 95.87% and 90.87%, respectively. When using laurylamine (LAM) as the collector at 20 °C, recovery efficiency of Cu, Al, Zn and Ag reached the respective maximum values with corresponding LAM dosage of 370 g/t, 740 g/t, 370 g/t and 1110 g/t, respectively. The flotation results indicated that using DO can achieve the better recovery of these metals from waste PCBs than using LAM. Finally, an environmentally friendly process for recovering valuable metals from waste PCBs using reverse flotation was considered.

A practical and convenient method for the synthesis of highly stable and small sized silver nanoparticles with narrow distribution from 3 nm to 15 nm is reported. Silver nitrate, stearic acid and hydrazine hydrate, were used as silver precursor, capping agents and reducing agents respectively. The formation of silver nanoparticles was observed by the change of color from milky white to dark red. The silver nanoparticles were characterized by transmission electron microscopy (TEM), UV–visible spectroscopy (UV–vis) and X-ray diffraction (XRD). The results demonstrated that the obtained metallic nanoparticles were single crystalline silver nanoparticles. The effects of the reaction temperature, the amount of stearic acid and ammonia on the particle size were investigated. The obtained silver nanoparticles are stable and will possibly be used in electronic applications. The preparation method is simple and may be extended to other noble metal for other technological applications.

Extrusion freeforming is a facile approach to produce complex 3D structures with controlled architecture and porosity. In this work, a new slurry system, mainly containing hydroxyapatite (HA) and sodium alginate (SA), has been used to fabricate porous hydroxyapatite scaffolds. After cross-linking in 5% calcium chloride (CaCl 2 ) solution for 24 h, HA–SA composite scaffolds were sintered at 1000–1300 °C for 2 h. The properties of HA–SA composite scaffolds before and after sintering have been investigated. The new slurry system has greatly improved the quality of porous hydroxyapatite scaffolds.

Chinese enterprises that conduct overseas investment projects encounter diverse challenges that emerge from political, economic, social, and environmental risks in the host countries. To better assess the overseas investment risks faced by Chinese enterprises, this study introduced and assessed novel aspects and an indicator system. Moreover, the “Technique for Order Preference by Similarity to Ideal Solution” (TOPSIS) method based on entropy weight was performed to generate a comprehensive assessment of China's foreign investment risk and natural resource potential in 63 “Belt & Road Initiative” (BRI) countries. This study aims to encourage Chinese enterprises to devise suitable overseas investment decision-making strategies concerning natural resource potential in host countries. A Geographic Information System (GIS) map was also created to assess the potential risks and opportunities for Chinese enterprises when making investment decisions in host countries. The findings indicate that the majority of countries in Central and Eastern Europe and other BRI countries such as Singapore, Malaysia, Nepal, Bhutan, Russia, Armenia, and the United Arab Emirates were the most suitable choices for Chinese enterprises engaging in overseas investment. Based on these results, Chinese enterprises could manage and execute BRI projects more effectively to minimise potential risks and maximise their investment benefits.

We employ STIRPAT (stochastic impact of regression on population, affluence, and technology) model to investigate the impact of natural resource depletion on energy use and carbon dioxide emissions for a panel of 56 “Belt & Road Initiative” (BRI) countries over 1990–2014. We utilize the Augmented Mean Group (AMG) panel estimator and Common Correlated Effects Mean Group (CCEMG) estimator for estimating our model. The results indicate that increasing natural resource depletion increases CO2 emissions and energy use, which shows that a 1% increase in natural resource depletion for our sample of BRI countries will increase CO2 emissions and energy use by 0.0286% and 0.0117%, respectively. To check the causal relationship among our variables, we employ the VECM Granger causality test. The causality results underscore feedback hypothetical links among CO2 emissions, energy use, economic growth, natural resource depletion, urbanization, and trade openness in the long run. Our results show a significant cross-sectional dependence and heterogeneity.

Metal–organic frameworks (MOFs) have emerged as new porous materials for capture and separation of binary gas mixtures. Tuning the metal sites in MOF structures has an impact on properties, which enhance affinity of gas adsorption and selectivity ( e.g. , surface area, cavity, electric field, etc .). The synthesis and characterization of a M-DABCO series (M = Ni, Co, Cu, Zn) of MOFs are described in this study. The experiments were conducted using multicomponent gas mixtures and the Ideal Adsorbed Solution Theory (IAST) was applied to determine the CO 2 /CH 4 selectivity. Experimental adsorption isotherms were fitted with a model equation to evaluate the characteristic adsorption energy (Isosteric, Qst) of this series. The Ni metal in the M-DABCO series reveals the best performance concerning CO 2 adsorption and CH 4 /CO 2 selectivity at ambient conditions based on IAST calculations. The combination of characterizations, calculations and adsorption experiments were used to discuss the metal impact on the adsorption sites in the M-DABCO series at ambient conditions.

Silver nanoparticle (Ag-np) is a new kind of antibacterial agent which is widely used in medical supplies. In this study, a simple approach is described to obtain Ag-doped HA scaffolds. Hydroxyapatite (HA) bone scaffolds with controllable pore size were fabricated by a micro-syringe extrusion system. Sintered HA scaffolds were then immersed in silver reaction hydrosol in order to get Ag-doped HA scaffolds. SEM and EDS shows a uniform distribution of silver nanoparticles on the surface of HA scaffolds. Such Ag-np doped HA scaffolds, displaying a good antibacterial activity against Escherichia coli (E. coli), are likely to prevent bone implant associated bacterial infections.

In this study, we report a simple and environment friendly method for synthesis of well dispersed and stable silver nanoparticles using semen cassiae extract as both reducing and stabilizing agents in aqueous solution without employing any other reducing and capping agents. The formation of silver nanoparticles was observed by change of color from light yellow to red and the UV–vis absorption spectroscopy. The effect of reaction time and semen cassiae amounts on the synthesis of silver nanoparticles was studied. The morphology of the as prepared silver nanoparticles was examined by using HRTEM, which showed that the silver nanoparticles were spherical in shape with a size distribution from 2 nm to 30 nm. The crystalline structure of the silver nanoparticles was confirmed by XRD analysis. The as synthesized silver nanoparticles were tested against Escherichia coli and the obtained data were indicative of good antibacterial properties of the materials. The method presented in this paper provides a very promising approach to synthesize other noble nanoparticles using renewable materials as reducing and capping agents. & 2014 Published by Elsevier B.V.

Available transfer capability (ATC) has been widely adopted as a crucial measure to guarantee free and reliable power trading. The existing literature generally evaluates the ATC of a power grid considering inelastic load. However, the impacts of responsive load have not yet been systematically explored, which underestimates the ability of demand side resources in ATC enhancement. Therefore, we propose a two-stage ATC evaluation framework in this paper integrating flexible demand response (FDR). In the first stage, i.e., a day-ahead market, a demand side bidding scheme is developed in which electricity users can make flexible choices to participate in demand response (DR) programs according to their preferences. In this paper, FDR is categorized into three typical patterns: (i) deferrable DR, (ii) switchable DR and (iii) adjustable DR. The objective is to minimize the total generation and dispatch costs, while respecting the constraints for FDR, the minimal accommodation of renewable energy, the inter-area power trading, etc. Then based on generation and demand side bidding, a day-ahead unit commitment model is formulated to schedule thermal generators, interchange power and FDR. In the second stage, a real-time ATC evaluation model based on the aforementioned unit commitment results is proposed to quantify the contributions of FDR on ATC enhancement. Case studies based on IEEE 14-bus system and a provincial power grid in China demonstrate that FDR can effectively improve real-time ATC by load shifting and peak shaving, and facilitate the accommodation of renewable energy.

Forests resources in Naltar Valley, Pakistan, are under continuous pressure because of limited access to off-farm opportunities and alternative source of energy. Therefore, this study underlines the essential demographic and socio-economic characteristics of rural livelihood on forest resource-dependent in the study area that explain the factors of forest dependency. To better estimate household forest dependency, we interviewed 248 randomly selected households using a semi-structured questionnaire. The binary logistic regression model was used to evaluate the potential determinants of forest resource dependency. The study revealed that age, education, household size, livestock income, agriculture income, and off-farm income were significantly influenced household dependency on forest resource, while other factors were not significant. Furthermore, the result shows that the income derived from the forests resources, agricultural products, livestock and off-farm activities contributes 39%, 33%, 16% and 12% respectively to the total household income. Forest income share from timber, firewood, honey, fodder, medicines, and fruits & vegetables are 46%, 52%, 1%, 1%, 0.41%and 0.47% respectively. Firewood has the most significant share in forest income and the primary source of energy mainly for cooking, and heating by the local community. To balance forest resource dependency and to conserve biodiversity, it is therefore essential to appreciate local communities by providing alternative income generation opportunities and provide them with alternative sources of domestic energy like hydroelectric power and biogas power. To this end, the proactive involvement of local communities in forest conservation is needed, as well as more plantation to meet the demand for fuelwood and thus reduce the pressure on forest resources. Keywords: Forest resource dependency, Fuelwood, Rural livelihoods, Logistic regression, Naltar Pakistan

Hollow spheres of AgI with an average radius of 100–200 nm have been prepared by a simple reaction between AgBr suspension and KI in the presence of gelatin. Gelatin played a decisive role as an inhibitor of the direct attack of I − ions to AgBr surfaces and coagulation of the growing AgI in producing the spherical AgI particles. The products were characterized by X-ray powder diffraction, transmission electron microscopy, UV–vis absorption spectroscopy and X-ray photoelectron spectra techniques. The band gaps are estimated to be 2.95 eV according to the results of optical measurements of the hollow spheres of AgI.

The 5 layer structured ZrO 2 –7 wt.% Y 2 O 3 –18 wt.% CeO 2 (C-YSZ) thermal barrier coatings (TBCs) by currently Plasma Spray (PS) and functionally graded TBCs system (FG-TBCs), composed of NiCoCrAlY bond coat (BC), C-YSZ/NiCoCrALY graded transition compound layer and a pure C-YSZ top coat, by recently developed Supersonic Plasma Spray system with dual powder feed ports were prepared. The experiment was performed to evaluate the thermal shock resistance of two different structured TBCs samples which were heated by a high heat flux of oxygen–acetylene flame to 1250 °C in a time interval of 10–15 s, and followed by water-quenching to ambient temperature using a multi-functional thermal shock tester in which 4 samples can be held simultaneously. The heating–cooling curves and surface morphology of specimens can also be observed by a CCD metalloscope and recorded on line through an accessorial computer system. The results show that thermal shock resistance of FG-TBCs was superior as its surface presents only little visible cracks after 200 cycles but 5 layer structured TBCs appear obviously delaminated after only 46 cycles.

The immobilization of Thiobacillus ferrooxidans on the activated carbon particles as support matrix was investigated. Cycling batch operation results in the complete oxidation of ferrous iron in 8 d when the modified 9 K medium is set to flow through the mini-bioreactor at a rate of 0.104 L/h at 25 °C. The oxidation rate of ferrous iron with immobilized T. ferrooxidans is 9.38 g/(L·h). The results show that the immobilization of T. ferrooxidans on activated carbon can improve the rate of oxidation of ferrous iron. The SEM images show that a build-up of cells of T. ferrooxidans and iron precipitates is formed on the surface of activated carbon particles.

Functional equations, in the form of fusion hierarchies, are studied for the transfer matrices of the fused restricted $A_{n-1}^{(1)}$ lattice models of Jimbo, Miwa and Okado. Specifically, these equations are solved analytically for the finite-size scaling spectra, central charges and some conformal weights. The results are obtained in terms of Rogers dilogarithm and correspond to coset conformal field theories based on the affine Lie algebra $A_{n-1}^{(1)}$ with GKO pair $A^{(1)}_{n-1}\; \oplus A^{(1)}_{n-1}\;\supset \; A^{(1)}_{n-1}$., 25 pages;latex file(epic.tex needed);Res.Rep.No 39;Tex Prob. fixed.

The generalization of the quantum inverse scattering method is used to solve exactly the eigenvalue problem of Belavin's Zn×Zn symmetric model. The Bethe ansatz equations and eigenvalues of the transfer matrix of the model are obtained, and the eigenstates are written down explicitly. Our derivations are relatively simple even for the case n=2. They also have the merit of providing simple formulae for the eigenstates of the transfer matrix.

Belavin's Zn × Zn symmetric model is studied. The transfer matrix of this model is exactly diagonalized using the quantum inverse scattering method. The Bethe ansatz equations and the eigenvalues are obtained.

A multicomponent coupled spin model, which is equivalent to a generalized Hubbard model is solved by the Bethe ansatz method. The continuum version of this generalized Hubbard model is shown to be the multicomponent fermionic nonlinear Schrodinger model.

The quantum nonlinear Schrodinger model with supermatrices, which have a structure (n − i, i) × (m − j, j), is studied. The Bethe ansatz equations and the eigenvalues of the model are obtained by using the quantum inverse scattering method.

The quantum Gelfand-Levitan equations for the multicomponent nonlinear Schrodinger model with supermatrices are derived, and the commutation relations for scattering data operators which are needed for calculating Green functions and correlation functions are given.