Applied Mechanics and Materials Vol. 483

Abstract: The using inductively coupled plasma etching techniques, the surface of fused silica was etched by CF4 as etching reaction gases. The results show that the fused silica surface scratches buried defects can be effectively removed with no replication effect, with the etching process proceeds, fused silica at 355nm laser light R: 1 under irradiated, the initial damage threshold of component surface is worth to an effective improved, damage resistance level of element surface more balanced, low damage threshold is worth to significantly improve.

Abstract: This paper reports on a simple and practicable biochip for polymerase chain reaction (PCR). The micro biochip (12mm×12mm) is a hybrid type which is composed of a polydimethylsiloxane (PDMS) cover with a hexagonal chamber and a glass substrate integrated with platinum (Pt) microheater and microsensor. Bubble formation has been reported as a big problem with PCR chips. In this paper we present a simple and practicable operation schedule to get a bubble free chip, in which a successful PCR process was guaranteed.

Abstract: A kind of enteric-coated pharmaceutical coating material, which can be dissolved in pH>5.5 medium, was successfully prepared by pre-emulsionsemi-continuous polymerization methods with equal molecular mass of methacrylic acid and ethyl acrylate as main raw materials. The effects of the initiator and chain transfer agent on the molecular weight and the performance of the emulsion were discussed. The obtained compound was used as the coating material of Lansoprazole capsule, and the dissolution rate was measured. The results show that polymethacrylat emulsion with 1.83×10⁵ of molecular weight was obtained when the dosage of the initiator and the chain transfer agent is 0.43% and 0.79% of the total monomer mass, respectively. The dissolution rate of Lansoprazole capsule coated polymethacrylat emulsion in the pH 6.8 medium was greater than 75%.

Abstract: This paper gives further discussions refer to the precision grinding of high performance ceramic materials through the two aspects of the Grinding Properties and depth.

Abstract: The chalcopyrite-type of CuIn_0.7Ga_0.3Se₂ nanoparticle was successfully prepared by mechanical alloying method (MA). The phase of the obtained powder was analyzed by x-ray diffraction (XRD), and its microstructure was analyzed by scanning electron microscope (SEM) and transmission election microscope (TEM). Subsequently, the sintering process of CIGS quarternary target was investigated. The result suggests that only CuIn_0.7Ga_0.3Se₂ phase exist in the powder with the rotation speed of 350 r/min and 2 hours mixing time by planetary ball milling. The particles were seriously agglomerated and the size of agglomerates was about 100 nm. Finally the as-made CIGS nanoparticles were used to fabricate CIGS target through both pressureless sintering and hot pressing methods. The hot pressing was fairly effective to increase the density of CIGS target. This fabricated target can be used for magnetron-sputtering deposition of CIGS absorbers.

Abstract: We studied moisture and volatile determination in bituminous coal samples using near-infrared (NIR) spectra. This research applied support vector machine (SVM) and discrete wavelet transform (DWT). Firstly, NIR spectra were pre-processed by DWT for fitting and compression. Then, DWT coefficients were used to build regression model with SVM. We used NIR spectra to determination moisture and volatile determination in coal samples separately. Through parameters optimization, the results show that DWT-SVM can obtain satisfactory performance for moisture and volatile determination in coal samples.

Abstract: Numerical simulation of sequential collision behavior of multi-particles during dynamic formation of Al-based coating on magnesium alloy by supersonic particles deposition demonstrated that continuous tamping effect from subsequent sprayed particles improved significantly compression ratio of former deposited particle and promote effectively deformation and spread out. Analysis to morphology and microstructure of Al-based coating on magnesium alloy by SEM and TEM elicited that subsequent sprayed particles generated two effects including erosion and compaction to former deposited layer of the coating, induced formation of high density dislocation, grains refinement and re-crystallization, which played work-hardening strengthening effect and fine crystal strengthening effect to Al-Si coating.

Abstract: An improved synthetic method based on glycosyl-1-H-phosphonate diesters has been developed for the preparation of O-d4T-5′-O-glycosyl-1″-phosphoramidate diesters, a kind of potential anti-HIV prodrugs. The target products were synthesized in high yields by using the CCl₄/Et₃N/amino acid methyl ester system.

Abstract: Cardanol, as one of components of cashew nut shell liquid (CNSL), is a mixture of 3-n-pentadecylphenol, 3-(pentadeca-8-enyl)phenol, 3-(pentadeca-8,11-dienyl)phenol and 3-(pentadeca-8,11,14-trienyl)phenol. It has both the characteristics of phenolic compounds and flexibility of aliphatic compounds. As a versatile industrial raw materials, it has been widely used as modifiers of the phenolic resin, rubber plasticizers, coatings and adhesives etc. Specially, cardanol-based surfactants have been reported using with long-chain alkyl moieties as lipophilic group in recent years. Herein, the application of this natural and renewable material to both academic and industrial research of cardanol-based surfactants will be discussed.

Abstract: A novel and efficient method for the preparation of α-D-mannose-1-phosphate has been developed. Phosphitylation of tetraacetylated D-mannose, hydrolysis yielded H-phosphonate monoester. Silylation of H-phosphonate, followed by oxidative coupling and hydrolysis gave protected D-mannose-1-phosphate. Finally, deprotection of tetraacetylated D-mannose-1-phosphate afforded D-mannose-1-phosphate in excellent yield.