亚麻化学加工对亚麻纺织品的影响——论述“亚麻专用助剂”在亚麻化学加工中应用的可行性

本文指出了现行亚麻化学加工技术存在化工原料用量多,成本大等弊端。并揭示了亚麻化学加工中大量使用NaOH等无机物质(即无机碱),使金属钠离子较多的充实到具有特殊纤维结构的亚麻纤维空腔与空隙中,致使亚麻纺织品手感硬挺有余而柔韧不足的奥秘。提出了应在亚麻化学加工中以有机碱(即有机化工原料)为主体,以达到亚麻脱胶工艺中加工出直接针织的针织用纱系列及服用性能优良的服装用布系列等产品。为此,笔者认为应从亚麻纤维的特殊结构着手,在亚麻化学加工中应用“亚麻专用助剂”,为亚麻行业实现清洁生产技术提供保障。

Effects of mask wall angle on matrix-hole shape changes during electrochemical machining by mask

The influences of the mask wall angle on the current density distribution,shape of the evolving cavity and machining accuracy were investigated in electrochemical machining(ECM) by mask.A mathematical model was developed to predict the shape evolution during the ECM by mask.The current density distribution is sensitive to mask wall angle.The evolution of cavity is determined by the current density distribution of evolving workpiece surface.The maximum depth is away from the center of holes machined,which leads to the island appearing at the center of cavity for mask wall angles greater than or equal to 90°(β≥90°).The experimental system was established and the simulation results were experimentally verified.The results indicate that the simulation results of cavity shape are consistent with the actual ones.The experiments also show that the repetition accuracy of matrix-hole for β≥90° is higher than that for β<90°.A hole taper is diminished,and the machining accuracy is improved with the mask wall angle increasing.

Mechanism of ultrasonic-pulse electrochemical compound machining based on particles

The electric double layer with the transmission of particles was presented based on the principle of electrochemistry.In accordance with this theory,the cavitation catalysis removal mechanism of ultrasonic-pulse electrochemical compound machining(UPECM) based on particles was proposed.The removal mechanism was a particular focus and was thus validated by experiments.The principles and experiments of UPECM were introduced,and the removal model of the UPECM based on the principles of UPECM was established.Furthermore,the effects of the material removal rate for the main processing parameters,including the particles size,the ultrasonic vibration amplitude,the pulse voltage and the minimum machining gap between the tool and the workpiece,were also studied through UPECM.The results show that the particles promote ultrasonic-pulse electrochemical compound machining and thus act as the catalyzer of UPECM.The results also indicate that the processing speed,machining accuracy and surface quality can be improved under UPECM compound machining.

Kinetics of Formic Acid-autocatalyzed Preparation of Performic Acid in Aqueous Phase

Performic acid （PFA） is an oxidant used in chemical processing, synthesis and bleaching. The macro kinetic models of synthesis, hydrolysis and decomposition of PFA were investigated via formic acid-autocatalyzed reaction. It was found that the intrinsic activation energies of PFA synthesis and hydrolysis were 75.2 kJ·mol^-1 and 40.4 kJ·mol^-1 respectively. The observed activation energy of PFA decomposition was 95.4 kJ·mol^-1. The experi-mental results indicated that the decomposition of PFA was liable to occur even at the ambient temperature. Both the spontaneous decomposition and the radical-introduced decomposition contributed to the decomposition of PFA.

Prediction of Process Trends Based on Neural Networks

In order to catch more process details in chemical processes, adynamic model for prediction of process trends is proposed bymodifying traditional time-series ANN (artificial neural networks)model with impulse response identification means. The applicationresults of the model is briefly discussed.

Parametric optimization of electrochemical machining of Al/15% SiC_p composites using NSGA-Ⅱ

Electrochemical machining（ECM） is one of the important non-traditional machining processes,which is used for machining of difficult-to-machine materials and intricate profiles.Being a complex process,it is very difficult to determine optimal parameters for improving cutting performance.Metal removal rate and surface roughness are the most important output parameters,which decide the cutting performance.There is no single optimal combination of cutting parameters,as their influences on the metal removal rate and the surface roughness are quite opposite.A multiple regression model was used to represent relationship between input and output variables and a multi-objective optimization method based on a non-dominated sorting genetic algorithm-Ⅱ（NSGA-Ⅱ） was used to optimize ECM process.A non-dominated solution set was obtained.

Microstructure and mechanical properties of Ti−Nb−Fe−Zr alloys with high strength and low elastic modulus

Zr was added to Ti−Nb−Fe alloys to develop low elastic modulus and high strengthβ-Ti alloys for biomedical applications.Ingots of Ti−12Nb−2Fe−(2,4,6,8,10)Zr(at.%)were prepared by arc melting and then subjected to homogenization,cold rolling,and solution treatments.The phases and microstructures of the alloys were analyzed by optical microscopy,X-ray diffraction,and transmission electron microscopy.The mechanical properties were measured by tensile tests.The results indicate that Zr and Fe cause a remarkable solid-solution strengthening effect on the alloys;thus,all the alloys show yield and ultimate tensile strengths higher than 510 MPa and 730 MPa,respectively.Zr plays a weak role in the deformation mechanism.Further,twinning occurs in all the deformed alloys and is beneficial to both strength and plasticity.Ti−12Nb−2Fe−(8,10)Zr alloys with metastableβphases show low elastic modulus,high tensile strength,and good plasticity and are suitable candidate materials for biomedical implants.

Effects of Different Processing Modes of Reconstituted Tobacco on Cigarette Quality

In order to explore the most suitable mode for the primary processing model of reconstituted tobacco, another two kinds of conditioning process schemes for reconstituted tobacco were designed based on the existing reconstituted tobacco processing method. Comparative analysis and evaluation were conducted for moisture content uniformity, intrinsic chemical compositions, casing uniformity, blending uniformity and sensory quality of the samples from the three kind of processing modes. The results showed that loosing and conditioning or the vacuum conditioning pretreatment of the reconstituted tobacco could effectively reduce the difference in moisture content during the blending, and improve the casing uniformity and blending uniformity. Moreover, the samples with the loosing and conditioning pretreatment had higher total sugar and reducing sugar contents, which indicated that the loosing and conditioning pretreatment method was more favorable for the improvement of the intrinsic quality of cigarettes. In addition, the three kinds of aromatic components contents of cigarettes using the loosing and conditioning pretreatment were higher,and the casing uniformity, blending uniformity and overall sensory quality of this pretreatment were all superior to that of the other two kinds of reconstituted tobacco pretreatment methods. The contents of total sugar, reducing sugar as well as the three kinds of aromatic components of cigarettes processed with vacuum conditioning pretreatment were all slightly lower than those of the existing methods, but the casing uniformity and blending uniformity were improved, while it showed small difference in the sensory quality with the existing processing method.

Development and Application of DCC Catalysts to Meet New Demands

The new generation of DCC catalysts, the DMMC/RMMC series catalysts developed by RIPP are introduced in this paper. The large molecule cracking ability is enhanced by increasing the portion of large pores; and the coke selectivity is improved by adjusting the acidity site density on the matrix surface, while the selective cracking reactions are increased. The sphericity of catalysts is improved by adopting new preparation method. The commercial application results have shown that applying DMMC/RMMC series catalysts with the mixed VGO, VGO plus AR, and hydrotreated VGO feed can increase the propylene yield by 2.43, 1.3 and 0.8 percentage points, respectively, as compared to the previous catalysts along with improvement in some products yields. The refining enterprises can make more profits after applying new series of DCC catalysts.

The Preparation of Fragrance and Health-Care Microcapsule Agent and Its Application on Fabrics

The technology of microcapsule was employed in this paper to prepare fragrant microcapsule agent, in which the core material was lavender oil, and the wall material polyurethane was formed from a reaction with 2, 4-tolylene diisocyanate （ TDI ） and poly （ ethylene glycol） （PEG） by interracial polymerization method. Through single factor and orthogonal experiments, the optimum technology conditions have been got as follows： the molecular weight of PEG 400, core/wall ration 1 ： 2, disperser sodium alginate （SA） 0.15%, emulsifier Poly（vinyl alcohol） （PVA） 1%, emulsifying speed 9 500 r/min, emulsifying time 5 min and reaction time 2 h. The microcapsule fragrant agent, prepared under the optimum conditions, was applied on the fabrics and a kind of good control-released fragrant fabric with health-care function was obtained.

Development and Commercial Application of Third Generation Resid Hydrotreating Catalysts

Based on the mechanism of resid hydrotreating reaction by coordinating the catalyst activity and stability, the diffusion mechanism and catalyst reactivity, the cost and catalyst performance, and the production and application requirements, the third-generation series catalysts for residue hydrotreating have been developed by Research Institute of Petroleum Processing, SINOPEC. The new series RHT catalysts possess higher activity for HDS, HDM and HDCCR performance as well as longer run length. The commercial results for application of these catalysts have demonstrated that the new catalyst system performs better than the reference ones.

Measurement Analysis in Electrochemical Discharge Machining （ECDM） Process： A Literature Review

Electrochemical discharge machining is considered to be a hybrid machining process that combines with EDM and ECM （electro chemical machining）, called ECDM. The material removal is based on two phenomena： electrochemical dissolution of the material and thermal erosion of electrical discharges that occur between the cathode ＆ anode electrodes. This process is better used for machining of non conducting materials efficiently. In this research paper shows that a brief literature review study of various measuring instruments used for analysis of various parameters of the electrochemical discharge machining process on various types of materials, tool material, input ＆ output parameters such as surface roughness, surface texture, material removal, tool wear etc..

Development of RSDS-III Technology for Ultra-Low-Sulfur Gasoline Production

The 3rd generation catalytic cracking naphtha selective hydrodesulfurization(RSDS-III) technology developed by RIPP included the catalysts selective adjusting(RSAT) technology, the development of new catalysts and optimized process conditions. The pilot plant test results showed that the RSDS-III technology could be adapted to different feedstocks. The sulfur content dropped from 600 μg/g and 631 μg/g to 7 μg/g and 9 μg/g, respectively, by RSDS-III technology when feed A and feed B were processed to meet China national V gasoline standard, with the RON loss of products equating to 0.9 units and 1.0 unit, respectively. While the feed C with a medium sulfur content was processed according to the full-range naphtha hydrotreating technology, the sulfur content dropped from 357 μg/g in the feed to 10 μg/g in gasoline, with the RON loss of product decreased by only 0.6 units. Thanks to the high HDS activity and good selectivity of RSDS-III technology, the ultra-low-sulfur gasoline meeting China V standard could be produced by the RSDS-III technology with little RON loss.

Optimization of assembly line balancing using genetic algorithm

In a manufacturing industry, mixed model assembly line(MMAL) is preferred in order to meet the variety in product demand. MMAL balancing helps in assembling products with similar characteristics in a random fashion. The objective of this work aims in reducing the number of workstations, work load index between stations and within each station. As manual contribution of workers in final assembly line is more, ergonomics is taken as an additional objective function. Ergonomic risk level of a workstation is evaluated using a parameter called accumulated risk posture(ARP), which is calculated using rapid upper limb assessment(RULA) check sheet. This work is based on the case study of an MMAL problem in Rane(Madras) Ltd.(India), in which a problem based genetic algorithm(GA) has been proposed to minimize the mentioned objectives. The working of the genetic operators such as selection, crossover and mutation has been modified with respect to the addressed MMAL problem. The results show that there is a significant impact over productivity and the process time of the final assembled product, i.e., the rate of production is increased by 39.5% and the assembly time for one particular model is reduced to 13 min from existing 18 min. Also, the space required using the proposed assembly line is only 200 m2 against existing 350 m2. Further, the algorithm helps in reducing workers fatigue(i.e., ergonomic friendly).

Enhancement of Adhesive Strength of Ultrahigh Molecular Weight Polyethylene Fibers Prepared by Polar Polymer Implantation

A new technique was proposed to enhance the adhesive strength of ultrahigh molecular weight polyethylene （UHMWPE） fibers. Polar polymer was implanted into UHMWE gel fibers during extracting process and can then be trapped on the surface of the fibers after subsequent ultra-drawing. The physical and chemical changes in the fiber structure were examined with scanning electron microscopy （SEM） and Fourier transform infrared （FTIR） spectroscopy. The mechanical and interfacial adhesion properties of UHMWPE fibers were investigated with tensile testing. The results showed that there were polar groups on the smface of pretreated UHMWPE fiber. The interracial shear strength of UHMWPE fibers with epoxy resin was greatly improved without sacrificing the excellent mechanical p^perties of fibers. After pretreated with ethylene/vinyl acetate copolymer （EVA）, the shear strength of the interface between fiber and epoxy resin increased from 1.06 to 2.49 MPa, while the integrated mechanical properties d the pretreated UHMWPE fibers were still optimal.

FEM analyses for influences of stress-chemical solution on THM coupling in dual-porosity rock mass

The models of stress corrosion, pressure solution and flee-face dissolution/precipitation were introduced. Taking a hypothetical nuclear waste repository in an unsaturated dual-porosity rock mass as the calculation objective, four cases were designed 1） the fracture aperture is a function of stress corrosion, pressure solution and free-face dissolution/precipitation; 2） the fracture aperture changes with stress corrosion and pressure solution; 3） the fracture aperture changes with pressure solution and free-face dissolution/precipitation; 4） the fracture aperture is only a function of pressure solution, and the matrix porosity is also a function of stress in these four cases. Then, the corresponding two-dimensional FEM analyses for the coupled thermo-hydro-mechanical processes were carried out. The results show that the effects of stress corrosion are more prominent than those of pressure solution and free-face dissolution/precipitation, and the fracture aperture and relevant permeability caused by the stress corrosion arc only about 1/5 and 1/1000 of the corresponding values created by the pressure solution and free-face dissolution/precipitation, respectively Under the action of temperature field from released heat, the negative pore and fracture pressures in the computation domain rise continuously, and are inversely proportional to the sealing of fracture aperture. The vector fields of flow velocity of fracture water in the cases with and without considering stress corrosion are obviously different. The differences between the magnitudes and distributions of stresses within the rock mass are very small in all cases.

Effects of Grape Processing on Antioxidant Capacity and ESI-MS Fingerprints of Grape Products

The antioxidant capacity and changes in chemical composition of two grape varieties, the new hybrid BRS-Carmem and the Bord6 grape （Vitis labrusca） and of their products （juice, wine and vinegar） were evaluated by several techniques. The DPPH method was used to measure the antioxidant capacity, whereas, the total phenolic contents （TPC） were measured by Folin-Ciocalteau method. Overall chemical composition was also monitored by ESI-MS fingerprints and UPLC-MS analysis. For both grape varieties, the highest （and similar） antioxidant capacity and TPC were observed for the wine and vinegar samples followed by the grapes and then the juices. In addition, ESI-MS fingerprints and UPLC-MS analysis in the negative ion mode indicated substantial changes in chemical composition from grape to juice and wine, and then to vinegar.

An Improvement on Si-etching Tetramethyl Ammonium Hydroxide Solution

An optimal concentration of the etching solution for deep etching of silicon, including 3% tetramethyl ammonium hydroxide and 0.3% (NH4)2S2O8, was achieved in this paper. For this etching solution, the etching rates of silicon and silicon dioxide were about 1.1μm·min-1 and 0.5nm·min-1, respectively. The etching ratio between (100) and (111) planes was about 34:1, and the etched surface was very smooth.

Effect of Extractive Removal on the Calorific Value of Brazilian Woods Residues

In wood processing, the production of residues is an unavoidable aspect to be considered. The use of wood residues is gaining importance due to the large amount generated and improper disposal, which can seriously harm environment. Burning of wood residues to energy generation is an increasingly usual practice. However, wood residues hold chemical substances that could be recovered before burning. These substances are the wood extractives, which may have many uses as natural dyes for fabrics, foods and cosmetics, as well as potential medicines. Thus, it is of great interest to study the effect of extractive removal on the calorific value of wood residues. In this work, the calorific value of three Brazilian wood species commonly used in sawmills （hymenaeacourbaril, jatoba; cedrelingacatenaeformis, cedroarana; tabebuiasp, ipe） and residues of urban trees pruning （caesalpiniaechinata, Brazil wood） were evaluated before and after extraction in hot water. In woods studied, the calorific value showed three patterns of behavior after removal of extractives soluble in hot water. For Brazil wood, the removal of extractives caused no significant change in calorific value. For cedroarana and jatoba, extractive removal led to a decrease in wood calorific value of 161.3 kcal.kg1 and 40. l kcal.kg^-1, respectively, which indicates that the extractives from these species have a positive energy potential. Finally, for ipe, the removal of extractives resulted in an increase in calorific value of wood （67.6 kcal.kg^-1）, which might encourage the recovery of extractives from wood residues before burning for energy generation.

Treatment of mine drainage generated by lead-zinc concentration plant

The purification efficiency in the treatment of the mine drainage generated by the mineral processing industry in Mengzi,Yunnan Project, China, was investigated, and the influences of the treated drainage on the mineral electrodes' electrochemical behaviors were tested. Experiments with different doses of polyacrylamide(PAM) and polymeric ferric sulfate(PFS) at different pH values were carried out, and the advanced purification by activated carbon(AC) was conducted. Compared with PFS, the better coagulant for removal efficiency is PAM, under the optimal conditions, the removals of Pb2+, Zn2+, Cu2+ and COD reduction from solution were 94.8%, 79.9%, 87.6% and 85%, respectively. In the advanced purification, the particle size of activated carbon and agitation time played important roles in the removal efficiency. Each pollute concentration could meet the emission standard of pollutants for lead and zinc industry(GB25466—2010). The wastewater without treatment affected galena and sphalerite electrochemical behaviors greatly, after treatment by the technology, the effects disappeared, which proved the reliability of the technology for wastewater treatment.