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ABSTRACTThis paper examines the relationship between supplier concentration and R&D investment of Chinese firms using the sample of all A-share listed companies on the Shanghai Stock Exchange and Shenzhen Stock Exchange from 2008 to 2015. Empirical results present the significant negative relationship between supplier concentration and firms’ R&D expenditure. Further analysis indicates that the weaker the firm’s market power, the stronger the negative impact of supplier concentration on the firm’s R&D investment. This paper enriches corporate R&D investments, supply chains, and market power literature. As developing countries deepen their participation in global supply chain networks and transform through technological upgrading, the findings of this paper have important practical implications for developing country firms to overcome R&D resistance and for policymakers to lead industrial development.

Reported herein is an in situ-generated hypervalent iodine-incorporating fluoroarylation of benzylidenecyclopropanes using commercially available HF·Py and aryl iodides as fluorine and aryl sources, respectively. The reaction proceeds via regioselective 1,2-fluoroiodination of a double bond followed by an iodonio-[3,3]-rearrangement of the formed cyclopropyl-I(III)species. The protocol offers facile access to valuable monofluorinated 1,1-bis-benzyl-alkenes with mild reaction conditions and moderate to good yields. The synthetic utility of the products was demonstrated by further transformations. Preliminary mechanistic studies were conducted.

Food spoilage leads to the annual huge wastage of food. There is a pressing need for safe, multifunctional food preservation packaging to curb this wastage and prevent contamination. In this study, we present a novel, cross-linked P-GL hydrogel film with a smooth surface microstructure, derived from polyvinyl alcohol (PVA), gallic acid (GA), and lysozyme (L). This hydrogel film serves as an exceptional packaging material for food preservation, displaying an ability to completely block UV light and efficiently impede the penetration of water vapor and O2. Remarkably, the P-GL hydrogel film exhibits a fracture strength of approximately 37.9 MPa, demonstrating superior water solubility, thermal stability, and mechanical properties. Also, this P-GL hydrogel film can effectively eliminate E. coliand S. aureus. The P-GL hydrogel film has proven to be successful in mitigating the spoilage of blueberries through coating and covering treatments, outperforming commercial plastic wrap. As a result, the shelf life of blueberries can be extended to 20 days. Our work provides innovative insights that could potentially drive the use of safe and multifunctional hydrogel films in the food preservation packaging industry.

This study was to evaluate the regulatory network among Galangin (Gal), oxidative stress, and renin–angiotensin system (RAS) in diabetic nephropathy (DN) in vitro. A cell model of DN was set up by exposing HK-2 cells to high glucose (HG, 30 mM) for 48 h and Gal was applied at 10 μM when needed. mRNA expression was analyzed by qPCR and protein level was detected by western blot. Malondialdehyde level and superoxide dismutase activity were evaluated by commercial kits. We analyzed cell viability by CCK8 assay and apoptosis by flow cytometry. DCFH-DA staining was conveyed for reactive oxygen species detection. HG induced RAS activation, oxidative stress, while inhibited cell viability. Gal suppressed oxidative stress-mediated apoptosis of HK-2 cells under the stimulation of HG via inhibiting RAS activation. Moreover, overexpression of AT1R, a RAS gene, could restrain the mitigative effect of Gal on cell injury. Furthermore, repression of RAS induced by AT1R knockdown partially reversed HG-induced PI3K/AKT/mTOR activation and oxidative stress in HK-2 cells. Also, AKT activation could antagonize Gal’s functional roles in renal cell damage. Collectively, Gal alleviates HG-induced oxidative stress injury of renal tubular epithelial cells through PI3K/AKT/mTOR signal via modulating RAS activation. This finding would help to better understand mechanism of DN development and support future studies.

Understanding yield potential, yield gap and the priority of management factors for reducing the yield gap in current intensive maize production is essential for meeting future food demand with the limited resources. In this study, we conducted field experiments using different planting modes, which were basic productivity (CK), farmer practice (FP), high yield and high efficiency (HH), and super high yield (SH), to estimate the yield gap. Different factorial experiments (fertilizer, planting density, hybrids, and irrigation) were also conducted to evaluate the priority of individual management factors for reducing the yield gap between the different planting modes. We found significant differences between the maize yields of different planting modes. The treatments of CK, FP, HH, and SH achieved 54.26, 58.76, 65.77, and 71.99% of the yield potential, respectively. The yield gaps between three pairs: CK and FP, FP and HH, and HH and SH, were 0.76, 1.23 and 0.85 t ha–1, respectively. By further analyzing the priority of management factors for reducing the yield gap between FP and HH, as well as HH and SH, we found that the priorities of the management factors (contribution rates) were plant density (13.29%)>fertilizer (11.95%)>hybrids (8.19%)>irrigation (4%) for FP to HH, and hybrids (8.94%)>plant density (4.84%)>fertilizer (1.91%) for HH to SH. Therefore, increasing the planting density of FP was the key factor for decreasing the yield gap between FP and HH, while choosing hybrids with density and lodging tolerance was the key factor for decreasing the yield gap between HH and SH.

Prostate cancer (PCa) remains the secondary highest cause of cancer‐related death in the United States in men. It has been reported that microRNAs can serve as key regulators in tumor development and progression in various cancers including PCa. In this study, we examined the effect of miR‐498 on proliferation, radiosensitivity, invasion, and migration of PCa cells. The proliferation of LNCaP and DU‐145 PCa cells with altered expression of miR‐498 was evaluated by MTT assay. The invasion and migration of LNCaP and DU‐145 PCa cells were assess by matrigel invasion assay and transwell migration assay. The protein expression level in PCa cells was examined by western blot. The function of miR‐498 on radiation‐induced apoptosis in LNCaP and DU‐145 PCa cells was detected by Caspase‐Glo3/7 assay. Forced expression of miR‐498 improved the proliferation, invasion and migration in PCa cells. Furthermore, miR‐498 decreased the sensitivity of PCa cells after ionizing radiation treatment. MiR‐498 reduced the radiation‐induced apoptosis in PCa cells by regulation of BAX and Bcl‐2 expression. Meanwhile, miR‐498 altered the expression of E‐cadherin, N‐cadherin, snail, and Vimentin in both LNCaP and DU‐145 PCa cells and regulated epithelial to mesenchymal transition (EMT). Further study showed that aberrant expression of miR‐498 changed the expression levels of phosphatase and tensin homolog and p‐AKT in LNCaP and DU‐145 PCa cells. In a summary, miR‐498 displayed important roles in tumor development and progression in PCa cells, and might act as a potential prognostic biomarker and predict radiotherapy response in PCa.

Selective laser melting (SLM) technology based on powder bed has been used to manufacture GH4169 samples. In the present work, taking Ni-based powders of GH4169 as experiment material, the good technological parameters of SLM were determined by analyzing the effect of the laser electric current, the scan speed ,the laser pulse width, the laser light frequency, the push powder thickness, the scan interval and the scanning way on Single-layer single-channel scanning, single-layer multi-channel scanning and multi-level multi-channel scanning. The effects of process parameters on the powder formability was analyzed. The cross-sections morphology and density of the block specimen prepared under the different SLM process parameter were studied. The optimal process parameters were the scanning speed of 150 mm/min, the laser pulse width of 5.0 ms, the push powder thickness of 0.15 mm, the scanning current of 140 A, the laser light frequency of 12Hz and the scan interval of 0.25mm.

•Validating the differential textural status of the hippocampus•Multiple sclerosis patients showed severe microstructural alterations in hippocampus•Dissimilar clinical-related radiomics features reflect distinct pathological changes•Specific imaging features can potentially assess disability and cognitive impairment

6-mercaptopurine (6-MP) is the first active metabolite inhibitor shown to suppress cancer cells. The aim of this study is to investigate the bioactivity of 6-MP derivatives and discover new anti-cancer agents. Four 6-mercaptopurine (6-MP) derivatives were synthesized and their anti-cancer activities were analyzed. All of the compounds showed anti-proliferative effects against HepG2 and A2780 cancer cells. Among the synthesized derivatives, 6-((naphthalen-2-ylmethyl)thio)-9H-purine (NMSP) which possessing a -naphthalene, showed better anti-cancer activity than other compounds, with an IC50 value 6.09μg/mL. NMSP could induce S phase cell cycle arrest and apoptosis in HepG2 cells. Western blot analysis indicated that NMSP induced apoptosis is mitochondria-dependent. The novel 6-MP derivative discovered in this study is a promising drug candidate to be used as an anti-cancer agent.

This paper presents a pendulous resonant MEMS biosensor for liquid detection based on SOI-MEMS technology. The biosensor consists of two electromagnetically driven and sensed resonant paddles working in the torsional mode. The differential output consisted by the two paddles provides the sensor reading. 1um thick SiNx is deposited on the electrodes by plasma enhanced chemical vapor deposition (PECVD), making the biosensor capable of working in liquid directly. In device fabrication, SOI-MEMS fabrication processes were utilized, where a new modified buffered hydrofluoric acid (BHF) solution was used to remove the buried oxide layer and release the paddles. High-current drive circuit and energy compensation circuit are designed to improve the Q-factor of the paddle in liquid. Experimental experiments show that the biosensor can distinguish the density of some liquid effectively．

This paper presents the design, fabrication and tests of an electro-magnetic vibrating ring gyroscope based on a control system and SOI-MEMS technology. The control system, including variable gain control (VGC), drive-frequency control and regulation module, is designed to improve mode matching. In device fabrication, and buffered hydrofluoric acid (BHF) solution is used to remove the buried oxide layer and release the suspended spring. Meanwhile, a compensate disk and negative photo resist (AZ303) coated on the backside of the wafer are employed to weaken the Lag and Footing effects during through-wafer etching process. The design of the gyroscope is optimized by FEA simulation and the fabricated devices show a rather good performance.

Interactions between civilizations and ethnic groups have generated a fusion of customs and lifestyles, with an important effect on plant genetic diversity. The loss of local species and varieties usually results in irreversible loss of the genetic diversity they contain, this has dangerously shrunk the genetic pool that is available for natural selection and art selection, and has consequently increased the vulnerability of agricultural crops to sudden changes in climate, and to the appearance of new pests. Currently, biotechnology and genomic selection have enabled the genetic alteration of crops, improved soil productivity, and enhanced weed and pest control, and benefit to the development of plant genetic diversity. For example, next generation sequencing (NGS) and bioinformatics, as the gold standard, they provide a powerful tool for discovery of domestication genes in crop plants and their wild relatives.The objectives of this article are to review the development of plant genetic diversity and summarize the research of biotechnology and genomics for plant. Then, we look forward and consider the significant of development of plant genetic diversity by biotechnology and genomics.

For at least the last 10,000 years humans have been selecting plants that performed better for them across a wide range of criteria including fruit size, number of fruit per plant, adaptation to specific environments, resistance to certain pests, and many other characteristics. As the demand for agricultural productivity continues to rise, there is an increasing pressure on plant breeders to develop new varieties that are higher yielding and able to produce in more challenging environments. In recent years, there has been a significant increase in the application of molecular genetic methods for assessing the conservation and use of plant genetic resources that provides the new ways for plant breeding, for example, the high-throughput sequencing technology provides the possibility of analysing high numbers of samples over smaller periods of time. Currently, molecular breeding is standard practice in many crops, and a diverse collection of plant genetic resources and these resources remain accessible to breeders is important.This article describes the exploitation of plant genetic resources and modern plant breeding, introduces the application of molecular techniques in plant breeding and perspectives the significant of development and utilization of plant genetic resources for plant breeding.

The appearance of agriculture roughly 10,000 years ago disrupted the ecological balance of numerous systems. Fortunately, the process of domesticating plants and animals and the spread of agriculture were slow enough to allow a new equilibrium to emerge. Plant genetic resources include primitive forms of cultivated plant species and landraces, modern cultivars, obsolete cultivars, breeding lines and genetic stocks, weedy types and related wild species, which provide the building blocks that allow classical plant breeders and biotechnologists to develop new commercial varieties and other biological products. Therefore, it is obviously very important to manage plant genetic resources for sustainable development in all of country. This article describes the management of plant genetic resources from conservation to utilization, introduces the status of international cooperation for sustainable development and perspectives that the significant plant genetic resources management for sustainable development in the future.

Crop genetic diversity is crucial for the environment, for feeding humanity and for sustainable agriculture development, which is providing genetic barriers against different biotic and abiotic stresses; however, it is being lost at an alarming rate. Fortunately, more and more people are conscious of the conservation and sustainable use of genetic resources goes far beyond avoiding the extinction of species, and the objective must be to conserve and use as much diversity as possible within each species. There is now a need for an integrated strategy for the conservation and management of crop genetic diversity and the organization of related information at several levels, for instance, at the highest level, it is necessary for entire agro-ecosystem, and also applies to the gene pools of individual crops at the interspecies level as well as at the intervarietal levels. This paper assesses the estimates methods on different genetic diversity in crop, introduces the status of crop genetic diversity, and prospects the significant conservation of crop genetic diversity for sustainable agriculture in the future.

A series of novel 1-substituted phenyl or glycosyl 1,2,3-triazoles was designed and synthesized by azide-alkyne 1,3-dipolar cycloaddition between 4,6-dimethoxy-2-[4-prop-2-ynyl)piperazin-1-yl] pyrimidine and each of different azides catalysed by in situgenerated Cu(I). The O-acyl protecting groups on glycosyl 1,2,3-triazoles were removed by triethylamine in wet methanol. Their chemical structures were established on the basis of corresponding 1H NMR, 13C NMR, MS and elemental analysis. The fungicidal activities of target compounds were evaluated in vitroagainst Fusarium omysporum, Physalospora piricola, Alternaria solani, Phytophthora capsici, Cercospora arachidicolaand Gibberella zeaeat 50 μg/mL. The bioassay results indicate that some of the compounds exhibited moderate but promising fungicidal activities. In particular, acetylated glucopyranosyl triazole displayed a good fungicidal activity against Physalospora piricola, which is equal to that of the positive control compound chlorothalonil.

As agriculture's impact on the Earth has been amplified by industrial farming, the functioning of ecosystems around the world is disruptive. The phenomena of agroecological environment are becoming worse and worse in the arid and semi-arid regions, which has become the predominant obstacle for agriculture development. Through understanding the character of perennial crops and developing them, however, would help us to deal with the multiple issues in agroecosystems, such as agroecological environmental conservation, economic benefits and so on. It also can provide multiple ecosystem services including a new solution to the long-standing problems of soil erosion and degradation associated with conventional annual small-grain cropping systems. This paper assesses the derivation of agroecology and agroecosystems, introduces the agroecological value of perennial crop, and prospects the significant utilization of perennial crop in the future.

As a powerful tool, biodiversity can be applied for assessing sustainability levels in agroecosystems as well as assessing both positive and negative effects of different agricultural activities and management strategies on the environment. It is the variety of life, including variation among genes, species and functional traits, which can increase the productivity of farming systems in a range of growing conditions, and also can maintain and increase soil fertility and mitigate the impact of pests and diseases. More diverse farming systems are generally more resilient in the face of perturbations, thus enhancing food security. For agriculture, biodiversity can be also expressed as planned (agricultural) and associated (para-agricultural and extra-agricultural) biodiversity, which reflect different functions of plants, animals and micro-organisms in agroecosystems. This paper introduces the categories of biodiversity in agroecosystems, assesses the functional biodiversity in sustainable agroecosystems, and prospects the significant of biodiversity in sustainable agroecosystems.

Carbohydrates, with broad-spectrum structures and biological functions, are key organic compounds in nature, along with nucleic acids and proteins. As part of our ongoing efforts to develop a new class of pesticides with novel mechanism of action, a series of novel N-glycosyl-1-pyridyl-1H-pyrazole-5-carboxamide was designed and synthesized viathe reactions of glycosyl methanamides and pyridyl-pyrazole acid. The compounds were characterized by 1H NMR and 13C NMR. The bioassay results indicate that some of these compounds exhibit moderate insecticidal activities and assessed as potential inhibitors of calcium channels. The modulation of voltage-gated calcium channels by compounds 4a and 5a in the central neurons isolated from the third instar larvae of Spodoptera exiguawas studied by whole-cell patch-clamp technique. In addition, compound 5a inhibits the recorded calcium currents reversible on washout. Experimental results also indicate that compound 5a did not release stored calcium from the Endoplasmic Reticulum. The present work demonstrates that N-glycosyl-1-pyridyl-1H-pyrazole-5-carboxamides cannot be used as possible inhibitors of calcium channels for developing novel pesticides.

Laser surface cladding of Ti6Al4V alloy by Ti+Al+C powders (Titanium and carbon powders with an atomic ratio of 1:1 were mixed with 20-60wt.% aluminum powders) was investigated using CO2 laser. TiC particles were in situ formed mainly during the solidification and sizes of TiC particles were varied according to different contents of aluminum powders in the Ti+Al+C system. The results show that the coating had good metallurgical bonding with substrate when Al content was 20% or 40%. The microhardness of coating is 738HV0.5 which was 2 times as that of the Ti6Al4V alloy approximately. The wear resistance of TiC/Al ceramic layer was approximately 3 times greater than that of the Ti6Al4V substrate. 1

This paper presents a method of low temperature wafer level adhesive bonding using non-photosensitive bisbenzocyclobutene (BCB) from Dow Co for resonant pressure sensor package. The bonding process is performed at the temperature below 250oC, with the pressure on the wafer 2-3 Bar in vacuum in a wafer bonding system. According to the bonding process, pre-bake time, pumping time, pressure placed on the sensor and the thickness of cross-linked layer are the most important factors. Experiments show that more than 95% of the area is successfully bonded, the hermeticity maintains well after thermal shock and long term tests, and the tensile strength of the fabricated bonds is up to 40MPa. The bonding technique was successfully tested in the fabrication process of resonant pressure sensor, and the results show that this bonding technique is a viable MEMS encapsulation technology for hermetically cavity sealing.

Laser surface cladding of Ti-6Al-4V alloy by Ti+C+Al powders (Titanium and carbon powders with an atomic ratio of 1:1 were mixed with 20-40wt.% aluminum powders) was investigated. TiC particles were in situ formed mainly during the solidification. Effect of Al content on the porosity and microstructure of the cladding layer was studied. The resultant microstructure in the modified surface layer was characterized and the micro-hardness on the cladding layers was measured, as well as the wear rates. The results show that the coating had good metallurgical bonding with substrate when the Al mass fraction in Al-Ti-C system is 30 %. The micro-hardness of coating is 802HV0.5 which is 2~3 times as that of the Ti-6Al-4V alloy approximately.

This paper presents a method of low temperature adhesive bonding and stress isolation for MEMS resonant pressure sensor hermetic packaging using non-photosensitive benzo-cyclo-butene (BCB) from Dow Co. According to the bonding process, pre-bake time, pumping time, pressure placed on the sensor and the thickness of crosslink layer are the most important factors. Stress isolation is designed to minimize thermal stresses to the resonant pressure sensor package. Experimental results show that this bonding process is a viable for MEMS resonant pressure sensor with the bonding temperature below 250℃, measured bonding strength more than 30MPa, the temperature drift less than 0.05%/℃ in the range of -40℃ to 70℃(10% of that without stress isolation), and the bonding strength maintains well after thermal treatments, handling, bench testing and implantations.

This paper According to the local approximate solution and finite series expression to the beam coefficients presented by Gouesbet and otherwise, we put forword a comprehensive recursive continued fraction algorithm and modify the defect of the existing algorithm, three key functions in scattering light intensity are recursively operated respectively, Mie scattering coefficient is obtained by using backward-recursive continued fraction algorithm, the highest recursive term is created automatically by computer and data fitting, the operation of angle function is carried out with Time forward-recurrence method, the beam coefficients equal to the local approximate solution and finite series expression, the relationship between scattering light intensity, gridling radius, particle size parameterer, relative refractive index and scattering angle is simulated based on MATLAB program and numerical calculation.

Protein S-nitrosylation plays a key and specific role in many cellular processes. Detecting possible Snitrosylated substrates and their corresponding exact sites is crucial for studying the mechanisms of these biological processes. Comparing with the expensive and time-consuming biochemical experiments, the computational methods are attracting considerable attention due to their convenience and fast speed. Although some computational models have been developed to predict S-nitrosylation sites, their accuracy is still low. In this work,we incorporate support vector machine to predict protein S-nitrosylation sites. After a careful evaluation of six encoding schemes, we propose a new efficient predictor, CPR-SNO, using the coupling patterns based encoding scheme. The performance of our CPR-SNO is measured with the area under the ROC curve (AUC) of 0.8289 in 10-fold cross validation experiments, which is significantly better than the existing best method GPS-SNO 1.0s 0.685 performance. In further annotating large-scale potential S-nitrosylated substrates, CPR-SNO also presents an encouraging predictive performance. These results indicate that CPR-SNO can be used as a competitive protein S-nitrosylation sites predictor to the biological community. Our CPR-SNO has been implemented as a web server and is available at http://math.cau.edu.cn/CPR -SNO/CPR-SNO.html.

It has been suggested that deregulation of activin signaling contributes to tumor formation. Activin signaling is blocked in cancer cells due to the complex formed by Cripto-1, activin, and activin receptor type II (ActRII). In this study, the authors used a mammalian two-hybrid system to construct a drug screening model to obtain a small molecular inhibitor capable of interrupting the interaction between Cripto-1 and ActRII. They screened 300 natural components and identified alantolactone. Data suggested that alantolactone induced activin/SMAD3 signaling in human colon adenocarcinoma HCT-8 cells. The authors also found that alantolactone exhibited antiproliferative function specific to tumor cells, with almost no toxicity to normal cells at a concentration of 5 µg/mL. Furthermore, they proved that the antiproliferative function of alantolactone was activin/SMAD3 dependent. These results suggest that alantolactone performs its antitumor effect by interrupting the interaction between Cripto-1 and the activin receptor type IIA in the activin signaling pathway. Moreover, screening for inhibitors of Cripto-1/ActRII is a potentially beneficial approach to aid in discovering novel cancer treatment.

Ni/TiC composites have been produced using laser induced self-propagating high-temperature synthesis. The chemical composition and microstructure were investigated by means of X-ray diffraction and scanning electron microscope. The sintered density and mechanical properties such as bending strength and micro-hardness were also measured. The results showed that the synthesized products were consisted of TiC and Ni phases, which indicated that the TiC was synthesized by the in-situ reaction. Moreover, the results revealed that the sintered density increased and the micro-hardness and bending strength of the synthesized products gradually decreased with the increasing of Ni contents.

Protein palmitoylation is an important and common post-translational lipid modification of proteins and plays a critical role in various cellular processes. Identification of Palmitoylation sites is fundamental to decipher the mechanisms of these biological processes. However, experimental determination of palmitoylation residues without prior knowledge is laborious and costly. Thus computational approaches for prediction of palmitoylation sites in proteins have become highly desirable. Here, we propose PPWMs, a computational predictor using Position Weight Matrices (PWMs) encoding scheme and support vector machine (SVM) for identifying protein palmitoylation sites. Our PPWMs shows a nice predictive performance with the area under the ROC curve (AUC) of 0.9472 for the S-palmitoylation sites prediction and 0.9964 for the N-palmitoylation sites prediction on the newly proposed dataset. Comparison results show the superiority of PPWMs over two existing widely known palmitoylation site predictors CSS-Palm 2.0 and CKSAAP-Palm in many cases. Moreover, an attempt of incorporating structure information such as accessible surface area (ASA) and secondary structure (SS) into prediction is made and the structure characteristics are analyzed roughly. The corresponding software can be freely downloaded from http://math.cau.edu.cn/PPWMs.html.

Selective laser sintering technology is used for manufacturing parts from 316 stainless steel powders. Experiments were carried out on a Nd:YAG laser machine (LMY400) with 400W. Powder is layered by a roller over the surface of a 100mm diameter build cylinder. Effects of processing parameter on the scan line width, the scan line height, the single layer structure and the multilayer structure are investigated. The results show laser power, scan speed and layer thickness have a great effect on the scan line width and line height. Furthermore, the stable and continuous vectors are formed with the increasing of the number of layers.

Silica particles coated with PA12 by emulsion polymerization were used as fillers to reinforce PA12 based composites prepared by selective laser sintering (SLS). The influences of the treated and untreated particles on the sintering behavior and mechanical properties of the laser sintered specimens were investigated. It was found that there were many uneven holes in the untreated composites. However, for the treated composites, due to the silica particle surfaces treated by emulsion polymerization, the absorbance of laser was improved and the particles dispersed well in the polymer matrix; a full dense structure was obtained and the properties were enhanced, such as the tend strength increased 30%, the maximum value was 34MPa; the tensile strength increased up to 125%, the maximum value was 44.2 MPa, comparing to the unfilled PA12. Drawing from the results, it can be confirmed that a full dense structure can be obtained and the PA12 matrix was strengthened and toughened when the silica particles were coated with PA12 by emulsion polymerization.

Nylon 12 composite powder with low melting point prepared by the method of solvent settling out as the basis material is modified with basis material added by all kinds of filling. With the ortho-design experiment method, the sintering process of nylon composite powder is optimized for sintering density and mechanical property of prototype parts. On this basis, the effects of the sintering process parameters on the properties of the parts are analyzed. The result shows this method can make nylon composite power with high powder density, precision and mechanical properties.

A multi-component polymer-coated molybdenum powder was chosen for selective laser sintering (SLS). A novel preparing method of polymer-coated molybdenum powder was presented. The effect of the process parameters on the part’s characteristics is investigated. Based on our study for dynamic laser sintering process of polymer-coated molybdenum powder, its laser sintering mechanism was reported as follows: at the early stage of laser sintering, the viscous flow is the major mechanism; during the laser sintering, the melting/solidification is the major mechanism. Furthermore, a model corresponding to the mechanism was discussed schematically, which could be used to explain the material migrating mode during laser sintering process.

An open-frame aluminophosphate, K[(Zn0.5Al0.5)2P2O8] (KZAPO), was rationally designed by a substitution design strategy and synthesized by a high-temperature molten salt method. Compared with the parent crystal of K[ZnBP2O8], KZAPO was characterized by similar 4 × 8 × 8 networks, a comparable short-wave ultraviolet transparency and a more regular tetrahedral frame with the mixing of (ZnO4)6–and (AlO4)5–anionic groups, highlighting the multifunctional roles that anionic group mixing played in structural and property modulations. In particular, KZAPO was characterized by a high thermal stability (over 850 °C) and a congruent-melting behavior, being conducive to practical applications.

A useful synthesis of 3-methylthio-6-methyl-pyrano[4,3-c]pyrazol-4(2H)-ones via 3-(bis-methylthio)methylene-5,6-dihydro-6-alkyl(aryl)-2H-pyran-2,4-dione with hydrazine as well as methyl and phenyl hydrazines is described and the mechanism of the formation is discussed. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:342–344, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10158

A useful synthesis of 3‐methylthio‐6‐methyl‐pyrano[4,3‐c]pyrazol‐4(2H)‐ones via 3‐(bis‐methylthio)methylene‐5,6‐dihydro‐6‐alkyl(aryl)‐2H‐pyran‐2,4‐dione with hydrazine as well as methyl and phenyl hydrazines is described and the mechanism of the formation is discussed. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:342–344, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10158

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