Transmittance and cathodoluminescence of AlN ceramics sintered with Ca3Al2O6 as sintering additive

Aluminum nitride ceramics were prepared by sintering with 0–4.8 mass% of Ca₃Al₂O₆ (C₃A) as a sintering additive. The transmittance in the range of 260–550 nm increased with increasing amount of C₃A. The cathodoluminescence intensity attributed to oxygen-induced defects decreased with increasing amount of C₃A. From the results, the increase of the transmittance in the range of 260–550 nm was considered to be related to the decrease of the oxygen-induced defect density.     

R & D Needs - Drying of Ceramics

New research and development needs for the drying of ceramics are prooosed. The researches on the ceramic drying are briefly reviewed and the role of the drying in the ceramic production process iS summarized. The drying must deal with molded materials and the problem is of significant difference from another drying with particulate materials. It means that the drying must be performed with keeping the molded feature and the insufficient completion of drying and the careless operation influence directly on the product quality The importnance of the R & D on the heat and moisture transfer. shrinking mechanism. the deformation behavior and the strain-stress formation in the molded clay issuggested. The subjects are also pointed out for the further improvement of the ceramic drying process and the precise design of molding with high quality.     

DRYING OF GRANULAR PARTICLES IN A MULTISTAGE INCLINED FLUIDIZED BED WITH MECHANICAL VIBRATION

A mathematical model for the drying rate of granular particles in a multistage inclined fluidized bed(IFB) is presented from the standpoint of simultaneous heat and mass transfer, with taking the effect of mechanical vibration added vertically into consideration.

Steady-state distributions for the temperatures and concentrations of the particles and the heating gas, and for the moisture content of the particles are numerically calculated based on the present model. The calculated results show fairly good agreement with the experimental data, which were obtained from the drying experiments of brick particles in a three-stage IFB using comparatively low temperature air(40-60°C) as the heating gas.

It has been found within the range of the experimental conditions employed that, the mechanical vibration added vertically enhances the over-all drying rate of the particles and its effect can be considered equivalent to an increase in the air velocity.     

Drying-Induced Strain and Stress: A Review

This paper is to review the works on strains and suesses in materials during drying.The strains and suesses are caused when temperature and moisture gradients are generated in mterials whose volume changes with heating and moisture removal. In such materials. failure and irregular deformion may be generated which affect considerably the qudity of the products after drying. In the first part. modeling procedure is introduced for the analysis of the strain-stress behavior in elaslic. viscous and visccelastic materials combined with heat and moisture transfer. An overview of the works on swains and stresses and drying characteristics are presented for malerials such as porous media. clay. sol-gels. agricultural products and foods in the second part. There are some materials that show both elasticity of the solid phase and viscosity of the fluid phase ( water or solvena∥ or viscoelasticiry. The suesses are often correlated with a suction pressure of fluids in pores and the flow rate is based on Dacy's equation for the elastic and viscous tnedia and a kind of viscoelastic media. The general canstitulive equalions. for suains and svesses are often analyzed with the stain behavior given by a function of moisturr for some media ai well. The emohasis is on the inuoduclion of comprehensive criteria for undersunding the problems of strain and stress development in materials subjected to drying.     

Dimethyl Fumarate Induces Apoptosis via Inhibition of NF-κB and Enhances the Effect of Paclitaxel and Adriamycin in Human TNBC Cells

Triple-negative breast cancer (TNBC) has the poorest prognosis of all breast cancer subtypes. Recently, the activation of NF-κB, which is involved in the growth and survival of malignant tumors, has been demonstrated in TNBC, suggesting that NF-κB may serve as a new therapeutic target. In the present study, we examined whether dimethyl fumarate (DMF), an NF-κB inhibitor, induces apoptosis in TNBC cells and enhances the apoptosis-inducing effect of paclitaxel and adriamycin. Cell survival was analyzed by the trypan blue assay and apoptosis assay. Protein detection was examined by immunoblotting. The activation of NF-κB p65 was correlated with poor prognosis in patients with TNBC. DMF induced apoptosis in MDA-MB-231 and BT-549 cells at concentrations that were non-cytotoxic to the normal mammary cell line MCF-10A. Furthermore, DMF inhibited NF-κB nuclear translocation and Survivin, XIAP, Bcl-xL, and Bcl-2 expression in MDA-MB-231 and BT-549 cells. Moreover, DMF enhanced the apoptosis-inducing effect of paclitaxel and adriamycin in MDA-MB-231 cells. These findings suggest that DMF may be an effective therapeutic agent for the treatment of TNBC, in which NF-κB is constitutively active. DMF may also be useful as an adjuvant therapy to conventional anticancer drugs.     

Decision Support for DCs Location and Distribute Range Planning: Case Study in Asia-Pacific Region

A major concern is to locate manufacturing plants and/or distribution centers to serve the needs of consumers widely and rapidly with reasonably distributive cost and flexible delivery time. The purpose of this research is to help enhance a decision support for three distribution center locations with different ranges of area in order that the distributors are able to serve appropriately the retailers in twelve large cities or capitals of the nine countries in Asia-Pacific region. The researcher applies the theory of supply chain and logistics management systems with Excel, Visual Basic and Genetic Algorithms programs to find the research results. The research results revealed that the interfaces of Excel, Visual Basic, and Genetic Algorithms programs helped decision support in distribution range selection for 3 distribution center locations. Each of which had different ranges of area for distribution with a rapidly, flexibly distributed time. However, variables resulting in a decision-making should be adjusted under certain circumstances for more reliable, specific needs.     

Programmed High‐Hole‐Mobility Supramolecular Polymers from Disk‐Shaped Molecules

In this paper a simple, casting solution technique for the preparation of two‐dimensional (2D) arrays of very‐high molecular weight (MW) 1D‐Pc supramolecular inorganic polymers is described. The soluble fluoroaluminium tetra‐tert‐butylphthalocyanine (ttbPcAlF) is synthesized and characterized, which can be self‐assembled to form 2D arrays of very‐high‐MW 1D‐Pc supramolecular inorganic polymers. High‐resolution transmission electron microscopy (HRTEM) demonstrates that the 1D‐ttbPcAlF, having a cofacial ring spacing of ～0.36 nm and an interchain distance of ～1.7 nm, self‐assembles into 2D‐nanosheets (～140 nm in length, ～20 nm in width, and equivalent to MW of 3.2 × 10⁵ g mol^?1). The film cast from a 1,2‐dichloroethane (DCE) solution shows a minimum hole‐mobility of ～0.3 cm² V^?1 s^?1 at room temperature by flash‐photolysis time‐resolved microwave conductivity (TRMC) measurements and a fairly high dark dc‐conductivity of ～1 × 10^?3 S cm^?1.     

A computer-aided design of EMC microstrip dipole arrays using nonlinear optimization techniques

This paper describes a method for designing electromagnetically coupled (EMC) printed dipole arrays. The advantages of EMC dipoles include greater bandwidth, higher efficiency, and an easier match to the feed lines, when compared to classically fed printed antennae. The excitation mechanism is provided by a strip transmission line embedded inside the substrate which couples energy parasitically to the microstrip antenna. Electromagnetically coupled microstrip dipoles have been investigated by empirical or approximate analysis techniques. As a result an approximate model has been derived for microstrip dipoles. The method is based on the method of moments solution to an integral equation derived from the approximate Green function for a grounded dielectric slab. The element lengths and offsets and the stub length of the EMC dipole array are determined by the direct search optimization method of Hooke and Jeeves. To show the feasibility of the proposed method, a mathematical formulation and numerical results are presented for Chebyshev arrays. © 1998 Scripta Technica, Electr Eng Jpn, 125(4): 60–66, 1998     

Development of cube-type SOFC stacks using anode-supported tubular cells

Tubular SOFCs have shown many desirable characteristics such as high thermal stability during rapid heat cycling and large electrode area per unit volume, which can accelerate to realize SOFC systems applicable to portable devices and auxiliary power units for automobile. So far, we have developed anode-supported tubular SOFCs with 0.8–2 mm diameter using Gd-doped CeO₂ (GDC) electrolyte, NiO-GDC anode and (La, Sr)(Co, Fe)O₃ (LSCF)-GDC cathode. In this study, a newly developed cube-type SOFC stack which consists of three SOFC bundles was designed and examined. The bundle consists of three 2 mm diameter tubular SOFCs and a rectangular shaped cathode support where these tubular cells are arranged in parallel. The performance of the stack whose volume is less than 1 cm³ was shown to be 2.8 V OCV and over 1 W at 1.6 V under 500 °C. Cathode loss factor due to current collection from cathode matrix was also estimated using a proposed model.