水牛服装革的脱毛、剖层、复灰工序的研究

本研究从水牛皮组织构造特点出发,针对水牛皮难于作软的问题,进行了脱毛、剖层、复灰方法的对比试验,其结果表明,采用小液比高浓度硫化钠溶液脱毛、片硝皮、复灰是水牛皮加工服装革较好的鞣前准备工艺。

复有理灰数的运算及其性质

本文在区间灰数和信息型灰数推广的基础上,将有理灰数进行了推广,给出了复有理灰数的定义,并讨论了它的运算及其性质。

复区间灰数的定义、运算及其性质

本文将区间灰数进行了推广,给出了复区间灰数的定义,并讨论了它的运算及其性质。

硅灰/粉煤灰复掺对水泥砂浆强度的影响

硅灰/粉煤灰复掺可大幅度提高砂浆的强度,当硅灰以8%的比例等量取代水泥,复掺经过机械活化15min的粉煤灰,粉煤灰掺量为10%时,复合砂浆28d抗折强度比基准砂浆抗折强度提高了45.9%,抗压强度比基准砂浆抗压强度提高34.6%,充分体现了硅灰/粉煤灰复掺的协同效应和复合材料的"超叠效应"(Synergistic)。

水稻施用含水泥窑灰钾复混肥效果研究

水稻施用含水泥窑灰钾复混肥效果研究结果表明,含水泥窑灰钾复混肥的肥效略优于含氯化钾复混肥和同等含量的尿素、过磷酸钙和氯化钾混配肥,但增产效果与其他2种肥料相比未达显著水平,比不施肥对照显著增产。

窑灰钾复混肥在甘薯大田栽培上应用效果试验

窑灰钾复混肥是龙岩市凯威肥业有限公司新开发生产的以水泥窑灰钾为主要钾原料的新型复混肥料。甘薯是大田作物中对钾元素需求量较大的作物,为探讨窑灰钾复混肥在甘薯大田栽培上的应用效果,观察施用窑灰钾复混肥和施用常用钾肥生产的复混肥(氯化钾复混肥、硫酸钾复混肥)对甘薯产量有何差异,笔者开展了窑灰钾复混肥和硫酸钾复混肥、氯化钾复混肥在甘薯大田栽培上的应用对照试验,结果表明施用窑灰钾复混肥和施用等含量的硫酸钾复混肥和氯化钾复混肥效果相当,同样能满足甘薯对钾元素的需求,提高甘薯产量,而且窑灰钾复混肥成本低,产投比大。

G_1⊙X^2⊕G_2＝G_3灰方程的解法

给出了灰方程ＸＧ１＝Ｇ２和Ｘ２＝Ｇａ，ｂ的一般求解方法，并在此基础上得出Ｇ１⊙Ｘ２Ｇ２＝Ｇ３灰方程的求解方法．

不浸酸铬鞣工艺平衡研究

研制了不浸酸铬鞣剂C—2000,皮在软化后直接用其进行鞣制,成革粒面紧实,但柔软度稍差。为使该鞣剂适用于轻革生产中,对不浸酸铬鞣工艺平衡进行了探讨。采用加强复灰的方法,平衡浸酸工序对胶原纤维的作用,并研究两者之间的关系。研究发现:加强复灰5～6h后,用C—2000进行鞣制,成革柔软性、面积变化与常规鞣制相当,抗张强度和撕裂强度比常规鞣制略高。

ANALYSIS ON GRAY NODES AND GRAYNESS DEGREE IN COMPLEX NETWORK

Based on the theory of complex network and gray system, the sugesstion that there exist two types of gray nodes in complex networks, Gray Node I and Gray Node II, is concluded. The first one refers to the existent unknown gray nodes, and the second the evolution gray nodes. The relevant definitions are also given. Further- more, grayness degree in complex networks is described and divided into two forms--the relative grayness degree （RGD） and the absolute grayness degree （AGD）, which are proved respectively.

Study on the Characteristics of Main Vegetation Communities in the Limestone Region of Taihang Mountain

[Objective] The aim was to study the characteristics of main vegetation communities in the limestone region of Taihang Mountain,so as to lay foundation for the further improvement of site conditions and the scientific breeding of vegetation used to restore the mountain field in limestone region.[Method] Based on the investigation of various vegetation communities in controlled test area,forbidden region and barren hillsides in Daqing Mountain basin,Beishui Valley,Mancheng County,Hebei Province,the difference among controlled region,forbidden region and barren hillsides could be found through data analysis and composite score,and the modes of vegetation communities in controlled region and forbidden region were compared to select predominant species of arbor,shrub and grass in limestone region.[Result] Under the similar site conditions,nutrient content and physical properties of soil in controlled region and forbidden region were superior to those of barren hillsides,and persimmon had high nutrient content and better physical properties compared with oriental arborvitae in controlled region;soil water maintenance and litter characters in controlled region and forbidden region improved more obviously than that of barren hillsides,and shrubbery in forbidden region was the most excellent,arborvitae and persimmon in controlled region the second;the biomass and the coverage rate of vegetation communities in controlled region and forbidden region were higher than those of barren hillsides,and those of shrubbery in forbidden region were better than tussock in closing hill,while persimmon was better than arborvitae in controlled region.The predominant species of arbor,shrub and herbage were obtained through composite score.[Conclusion] From the aspects of soil nutrient,physical properties,soil water maintenance,litter characters,vegetation biomass,canopy density and coverage,controlled region and forbidden region were superior to barren hillsides,and the selection of predominant species of arbor,shrub and herbage considered both ecological and economic benefits.

新疆山羊高尔夫手套革的研制

本文讨论了用新疆小山羊皮生产山羊高尔夫手套革的工艺操作要点.开发研制山羊高尔夫手套革的主要技术指标:革身丰满柔软,手感好,色泽浅淡,油润感强,有较大的延伸率.要达到上述要求,技术关键是适度消解网状层胶原纤维和弹性纤维,彻底松散乳头层原纤维组织.加强复灰,增强软化,和良好的白色复鞣剂和加脂剂.

Photocatalytic activity of TiO_2 supported SiO_2-Al_2O_3 aerogels prepared from industrial fly ash

A ternary composite of TiO2 and a SiO2-Al2O3 aerogel with good photocatalytic activity was prepared by a simple sol-gel method with TiO2 nanoparticles and SiO2-Al2O3 aerogels derived from industrial fly ash.The structural features of the TiO2/SiO2-Al2O3 aerogel composite were investigated by X-ray powder diffraction,Fourier transform infrared spectroscopy,transmission electron microscopy,gas adsorption measurements and diffuse reflectance UV-visible spectroscopy.The optimal conditions for photocatalytic degradation of 2-sec-butyl-4,6-dinitrophenol（DNBP],included an initial DNBP concentration of 0.167 mmol/L at pH = 4.86 with a catalyst concentration of 6 g/L,under visible light irradiation for 5 h.A plausible mechanism is proposed for the photocatalytic degradation of DNBP.Our composite showed higher photocatalytic activity for DNBP degradation than that of pure TiO2.This indicates that this material can serve as an efficient photocatalyst for degradation of hazardous organic pollutants in wastewater.

Optimization of machining parameters in drilling hybrid aluminium metal matrix composites

Taguchi method with grey relational analysis was used to optimize the machining parameters with multiple performance characteristics in drilling hybrid metal matrix A1356/SiC-mica composites. Experiments were conducted on a computer numerical control vertical machining centre and Lzs orthogonal array was chosen for the experiments. The drilling parameters namely spindle speed, feed rate, drill type and mass fraction of mica were optimized based on the multiple performance characteristics including thrust force, surface roughness, tool wear and burr height （exit）. The results show that the feed rate and the type of drill are the most significant factors which affect the drilling process and the performance in the drilling process can be effectively improved by using this approach.

Biotribological behavior of ultra high molecular weight polyethylene composites containing bovine bone hydroxyapatite

Wear particles of ultrahigh molecular weight polyethylene （UHMWPE） are the main cause of long-term failure of total joint replacements. Therefore, increasing its wear resistance or bioactivity will be very useful in order to obtain high quality artificial joints. In our study, UHMWPE composites filled with the bovine bone hydroxyapatite （BHA） were prepared by the method of compression moulding. A ball-on-disc wear test was carried out with a Universal Micro-Tribometer to investigate the friction and wear behavior of a Si3N4 ceramic ball, cross-sliding against the UHMWPE/BHA composites with human plasma lubrication. At the same time, the profiles of the worn grooves on the UHMWPE/BHA surface were scanned. The experimental results indicate that the addition of BHA to UHMWPE had a significant effect on the biotribological behavior of UHMWPE cross-sliding against the Si3N4 ceramic ball. The addition of BHA powder enhanced the hardness and modulus of elasticity of these composites and decreased the friction coefficients and wear rates under conditions of human plasma lubrication. When the added amount of BHA powders was up to 20%-30%, UHMWPE/BHA composites demonstrated the designed performance of the mechanical properties and biotribological behavior.

Esophageal granular cell tumors:Report of 9 cases and a literature review

Esophageal granular cell tumors(GCTs) are rare tumors of the esophagus.We evaluated the clinical and pathologic features of 9 esophageal GCT patients(5 men and 4 women) from our institute and reviewed the related disease literature.Patient age ranged from 25 to 53 years(mean:41 years).All the patients were asymptomatic or presented with non-specific symptoms.Most GCTs occurred in the distal esophagus and were less than 6 mm in diameter.Computational analysis showed that the average gray-scale endoscopic ultrasound images of esophageal GCTs were greater than that of esophageal leiomyomas.Eight patients were treated by endoscopic resection,and 1 patient underwent surgical excision.No post-therapy recurrence or metastasis developed during follow-up(mean:36.4 mo,range:1-72 mo).

Leaching behaviors of calcium and magnesium in ion-adsorption rare earth tailings with magnesium sulfate

The leaching behaviors of calcium and magnesium in the rare earth tailings leached with magnesium sulfate using deionized water,CaCl2 solution and lime water were investigated.Experimental data indicated that magnesium in the tailings was easy to be leached out since most of the magnesium was in the form of water-soluble phase.Most of calcium in the lime water was electrostatically adsorbed on the clay mineral of the tailings,and the water-soluble magnesium was also gradually converted into exchangeable phase because of back-adsorption of Mg2+on the clay mineral with increasing the pH values.When the liquid-to-solid ratio was 0.80,the contents of readily-available magnesium and calcium were 104.4−207.6 and 201.7−1426.3 mg/kg,respectively,which could meet the requirements for plants.These results suggest a promising route for the environmental remediation of ion-adsorption rare earth ore after in-situ leaching.

Hydration mechanism of low quality fly ash in cement-based materials

The hydration mechanism of low quality fly ash in cement-based materials was investigated. The hydration heat of the composite cementitious materials was determined by isothermal calorimetry, and the hydration products, quantity, pore structure and morphology were measured by X-ray diffraction(XRD), thermalgravity-differential thermal analysis(TG-DTA), mercury intrusion porosimetry(MIP) and scanning electron microscopy(SEM), respectively. The results indicate that grinding could not only improve the physical properties of the low quality fly ash on particle effect, but also improve hydration properties of the cementitious system from various aspects compared with raw low quality fly ash(RLFA). At the early stage of hydration, the low quanlity fly ash acts as almost inert material; but then at the later stage, high chemical activity, especially for ground low quality fly ash(GLFA), could be observed. It can accelerate the formation of hydration products containing more chemical bonded water, resulting in higher degree of cement hydration, thus denser microstructure and more reasonable pore size distribution, but the hydration heat in total is reduced. It can also delay the induction period, but the accelerating period is shortened and there is little influence on the second exothermic peak.

Microstructure and mechanical properties of aluminium metal matrix composites with addition of bamboo leaf ash by stir casting method

Al-4.5%Cu alloy was used as a matrix at2%,4%and6%of bamboo leaf ash(BLA)which was extruded from agro waste and was used as reinforcement.The composite which was fabricated by stir casting method possessed superior properties due to an effective bonding between matrix and reinforcement particles.The fabricated composite specimens were subjected to various tests to determine the mechanical properties such as density,porosity,hardness and tensile strength.The results were compared with basic matrix alloy.Furthermore,the OM,SEM with EDAX and XRD analyses were carried out to analyze the dispersion of the reinforced particles in the selected matrix alloy.It was observed that the homogeneous distribution of BLA particles in composites was intragranular in nature.Moreover,it was also observed that BLA particles were well bonded with matrix alloy with clear interface.It was also found that the density decreased with increase in mass fraction of BLA particles and porosity increased with increase in mass fraction of BLA particles.The hardness and tensile strength were increased up to4%of BLA in the composite,with a further increase in BLA content the hardness and tensile strength decreased.

Preparation and characterization of chitosan/nano-hydroxyapatite composite used as bone substitute materials

Chitosan/nano-hydroxyapatite composites with different weight ratios were prepared through a co-precipitation method using Ca（OH）2, H3PO4 and chitosan as starting materials. The properties of these composites were characterized by means of TEM, IR, XRD, TGA, burn-out tests and universal matertial testing machine. The results showed that the HA synthesized here was poorly crystalline carbonated nanometer crystals and dispersed uniformly in chitosan phase and there was no phase-separation between the two phases. The addition of n-HA resulted in a decrease of decomposing temperature of chitosan. Because of the interactions between chitosan and n-HA, the mechanical properties of these composites were improved, and the maximum value of the compressive strength was measured to be about 120MPa corresponding to the chitosan/n-HA composite with a weight ratio of 30/70.

Production and characterization of rich husk ash particulate reinforced AA6061 aluminum alloy composites by compocasting

Rice husk ash(RHA) is a potential particulate reinforcement to produce aluminum matrix composites(AMCs)economically.Compocasting method was applied to produce aluminum alloy AA6061 reinforced with various amounts(0,2%,4%,6%and 8%,mass fraction) of RHA particles.The prepared composites were characterized using X-ray diffraction and scanning electron microscopy.X-ray diffraction patterns of AA6061/RHA AMCs revealed the presence of RHA particles without the formation of any other intermetallic compounds.The scanning electron micrographs showed a homogeneous distribution of RHA particles all over the aluminum matrix.Intragranular distribution of RHA particles was observed.Further,RHA particles were bonded well with the aluminum matrix and a clear interface existed.The reinforcement of RHA particles enhanced the microhardness and ultimate tensile strength(UTS) of the AMCs.The tensile behavior is correlated to the microstructure of the AMCs.