In Vivo Histocompatibility Evaluation of Polyurethane Membrane Modified by Superfine Silk-fibroin Powder

In this study, a novel polyurethane membrane, modified by superfine silk-fibroin powder, was prepared for small-diameter vascular grafting. Scanning electron microscopy, transmission electron microscopy, and histological examination were applied to evaluate histocompatibility of this polyurethane membrane. The polyurethane membrane was compared with polytetrafluoroethylene material. A pseudomembrane and gap formed between polytetrafluoroethylene and the surrounding tissues, and no cells infiltrated or grew into the polytetrafluoroethylene material. On the contrary, superfine silk-fibroin powder/polyurethane blend membrane merged tightly with the surrounding tissues without gaps, and cells infiltrated and grew into the material. Moreover, the negative effects of superfine silk-fibroin powder/polyurethane blend membrane on cells were less than those of its polytetrafluoroethylene counterpart. Our findings indicated that the superfine silk-fibroin powder/polyurethane blend membrane has better histocompatibility than polytetrafluoroethylene membrane. It is concluded that the superfine silk-fibroin powder/polyurethane blend membrane is a promising biomaterial for small-diameter prosthesis.

Preparation of Superfine Fe_3O_4 Cubic Powders

A kind of superfine Fe_3O_4 cubic powder has been prepared chemi- cally.Its formation is related with the concentration of Na^(+1) in the chemical reaction.Given the same particle size,a superfine Fe_3O_4 cubic powder has a higher H(?) and lower σ,than one made up of spherical Fe_O_4.

Preparation and Characterization of CeO_2 Superfine Powder

The CeO_2 superfine powder was prepared by the co-precipitation method, using the industrial grade Ce_2(CO_3)_3 and NH_4HCO_3 as starting material and precipitating reagent, respectively. The precipitated precursons and the calcinated products were characterized by the thermogravimetric analysis/thermoanalysis (TGA/DTA), X-ray diffraction analysis (XRD) and transmission electron microscopy (TEM). The results show that using NH_4HCO_3 as a precipitating reagent, the precipitate decomposed full as it was heated to 360 ℃. The CeO_2 superfine powder formed by calcinating the precipitate belongs to a cubic CaF_2-type structure and has the first mean particle diameter 140 nm and second mean particle diameter 630 nm. The CeO_2 powder particles aggregate and grow with raising the calcination temperature.

Protective effects of Purendan superfine powder on retinal neuron apoptosis in a rat model of type 2 diabetes mellitus

This study sought to investigate the effects of Purendan superfine powder comprised of Momordica charantia, Radix Ginseng, and Radix Salviae Miltiorrhiae on neuronal apoptosis and expression of bcl-2, bax, and caspase-3, which are retinal apoptosis-associated factors in rats with diabetes mellitus induced by continuous intraperitoneal injection of streptozotocin. The results showed that Purendan superfine powder could upregulate the expression of bcl-2 protein and mRNA, and downregulate the expression of bax and caspase-3 in the retina of diabetes mellitus rats. In addition, Purendan superfine powder was shown to reduce the number of apoptotic neurons. Our experimental findings indicate that Purendan superfine powder can inhibit neuronal apoptosis in the retina of diabetes mellitus rats and has protective effects on diabetic retinopathy.

Improving performance of recycled aggregate concrete with superfine pozzolanic powders

Phosphorous slag （PHS）, ground granulated blast-furnace slag （GGBS） and fly ash （FA） were used as replacements of Portland cement to modify the microstruc^xe of recycled aggregate concrete （RAC）. A new manufacturing method named ＂W3T4＂ was proposed to improve the performances of interracial transition zone （ITZ） between recycled aggregate and mortar. The mechanical properties and the durability of RAC were tested, which show that this new manufacturing method improves the properties of RAC, and the GGBS with finest size makes a great contribution to the performance of RAC due to its better filling effect and much earlier pozzolanic reaction. Combined with GGBS, the effects of PHS on the retardation of setting time can be alleviated and the synergistic effect helps to make a more compact RAC. For the RAC with 25% of the recycled aggregate （RA） replacement and 10% PHS ＋ 10% GGBS additives, the compressive strength increases by 25.4%, but the permeability decreases by 64.3% with respect to the reference concrete made with nature aggregates. The micro-mechanisms of these improvements were investigated by the scanning electron microscope （SEM）. The SEM images show that the new manufacturing method, adding superfine pozzolanic powders and super-plasticizer benefits, makes a much denser ITZ in RAC.

Characteristics of Superfine Green Tea Powder and Its Application in Food Industry

Superfine green tea powder is a new kind of tea product that can be eaten directly.It provided most of the benefits of whole green tea leaves,with all of the bioactive ingredients.This paper highlighted the characteristics and health benefits of superfine green tea powder,and its applications in food industry.

Mechanical Properties of Small-diameter Superfine Silk Powder/Polyurethane Vascular Graft Reinforced by Tubular Knitted Fabric

In this paper,a kind of composite microtube,which is made from superfine silk powder and polyurethane,reinforced by polyster and spandex tubular fabrics,was examined.The cross-section of composite microtubes were microporous,and micropores were uniform distributed,the inner surface was relatively smooth.The results showed that the wall thickness of composite microtubes increased,which led to the strength,the breaking work and the initial modulus incresead;that the spandex content increased brought about the initial modulus and the breaking work decreased,but the breaking extension and the breaking load were firstly increased and then decreased;and all the mechanical properties decreased as the SFSP content increased.

Effect of Superfine Slag Powder on HPC Properties

A superfine slag powder (SP) made from granulated blast furnace slag incorporating activators by using special millingtechnique, was used as supplementary cementitious material in high performance concrete (HPC), replacing part ofthe mass of normal Portland cement. The effects of the SP on the workability, mechanical and crack self-healingproperties of HPC were studied. The hydration process and microstructure characteristics were investigated by X-raydiffraction (XRD) and scanning electron microscopy (SEM) techniques, respectively. The crack self-healing capacitywas evaluated by Brazilian test. The test results indicate that the SP has especially supplementary effect on waterreducing and excellent property of better control of slump loss. The concrete flowability increases remarkably withthe increase of SP replacement level in the range of 20% to 50%. The compressive and splitting tensile strengthsof HPC containing SP are higher than the corresponding strength of the control concrete at all ages. The crackself-healing ability is highly dependent on SP content of HPC.

Study on Test Methods for Flow Ability of Superfine Powder Extinguishing Agent

According to the physical and chemical characteristics of superfine powder extinguishing agent,three test methods are selected to measure the flow ability.By studying and comparing various test methods,apparatus and conditions,the optimum method and conditions to test flow property of superfine powder extinguishing agent are confirmed.

Synthesis of LaF_3 superfine powder by microwave heating method

LaF3 superfine powder was synthesized from La（CH3COO）3 and NH4F by micro wave heating method,using ethanol or pure water as dispersants respectively. Th e results of XRD and SEM indicate that the superfine powder has high purity,reg ular particle shape and narrow distribution of granularity. The granularity of t he best sample is in the range of 100200 nm.The influence of different dispersants on the crystal degree and microstructure was discussed. After the su perfine powder was formed into a slice at pressure of 2560 MPa,its ele ctrochemical impedance spectroscopy was tested by electrochemical impedance spec troscopy（EIS） measurement. The result shows that the grain refining of LaF3 po wder increases its ionic conductivity. Compared with traditional preparation met hods of LaF3 powder,the advantages of microwave heating method were summarize d.

The Feasibility of Basalt Rock Powder and Superfine Sand as Partial Replacement Materials for Portland Cement and Artificial Sand in Cement Mortar

The research gap on the feasibility of basalt rock powder(BRP)and superfine sand(SS)in preparation of cement mortar is significant.This study examines probable changes occurred in the modified cement mortar due to incorporation of certain quantity of basalt rock powder and superfine sand in mixture proportion.The cement mortar included Portland cement,artificial sand and water as principal mixture constituents.Then,basalt rock powder and superfine sand were added as partial replacement materials for Portland cement and artificial sand respectively.Therefore,replacement percentages were 10%,15%,20%,25%and 30%when the basalt rock powder replaced Portland cement and in case the artificial sand was replaced by superfine sand,10%,20%,30%,40%and 50%.Then,the strength indexes such as flexural strength,compressive strength,ultrasonic pulse velocity and dynamic elastic modulus were investigated.The results show that the presence of basalt rock powder in mixture proportion increased the flexural and compressive strengths of cement mortar however the cement mortar that contained superfine sand illustrated inadequate mechanical performance as flexural and compressive strengths decreased remarkably.Moreover,when basalt rock powder and superfine sand were included together in mixture proportion,the cement mortar’s mechanical performance declined compared to that of the reference cement mortar.Despite the fact that basalt rock powder and superfine sand weakened the cement mortar’s mechanical properties,it was found that they can be added into the cement mortar as partial replacement of Portland cement and artificial sand in the following ratios:from 10%to 25%when basalt rock powder replaces Portland cement and from 10%to 20%when artificial sand is replaced by superfine sand.

微晶石墨取代炭黑作为橡胶补强剂应用研究

针对微晶石墨(MG)作为橡胶补强剂分散性差的问题,选用与石墨烯有相近表面张力的25%乙醇溶液作为球磨溶剂,通过球磨法制备出了中位粒径为1.209μm的MG超细粉,以其部分取代炭黑(CB)作为天然橡胶(NR)补强剂,得到了力学性能更优的NR/CB/MG复合材料.利用场发射扫描电镜(SEM)表征了MG和CB在NR基体中的分散情况,研究了MG粒径和取代量对NR/CB/MG复合材料性能的影响规律.结果表明,适量的MG可促进CB在NR基体中的分散、缩短NR/CB/MG复合材料的正硫化时间;MG的粒径越细,NR/CB/MG复合材料的力学性能越好,与NR/CB复合材料相比,其拉伸强度、撕裂强度、100%定伸应力和300%定伸应力分别提高6.3%、7.5%、8.4%和6.4%,疲劳温升和永久变形率分别降低2.5%和44.7%.

响应面法优化超微岩茶粉糙米无糖蛋糕的研制

利用超微粉碎技术制得超微武夷山岩茶粉,以蛋糕粉和糙米粉为主要原料,添加超微岩茶粉和赤藓糖醇制作一款戚风蛋糕。通过单因素试验,考查超微岩茶粉、糙米粉、赤藓糖醇和蛋清添加量对蛋糕感官评价和质构的影响,并在单因素试验结果的基础上,以综合评分为指标,利用响应面法优化确定蛋糕最佳工艺配方为:以糙米粉与蛋糕粉总质量为基准,按烘焙百分比计,糙米粉添加量78.3%,超微岩茶粉添加量5.6%,赤藓糖醇82.5%,蛋清添加量224.8%。以此配方制得的超微岩茶粉糙米无糖蛋糕呈淡棕绿色,组织松软细腻,茶香馥郁且具稻米香气,营养价值高于普通戚风蛋糕。

超微粉碎对水果番茄粉理化性质与结构特性的影响

为研究超微粉碎技术对水果番茄粉品质的影响,对水果番茄干进行粉碎处理得到粗粉(40目)、细粉(100目)、超微粉(200目)3种粉体,运用粒度分析、扫描电镜、X射线衍射图谱、傅里叶红外光谱、差式量热扫描等技术测定粒度、比表面积、微观结构、热性质等物理、化学和结构特性。结果表明,水果番茄超微粉的粒径达11μm且流动性较好,其亮度较粗粉和细粉显著提高(P<0.05),水溶性、持水力、膨胀度、乳化性、稳定性、持油力、休止角和滑角显著高于细粉与粗粉(P<0.05),润湿性、复水性、堆积密度、振实密度显著低于细粉和粗粉(P<0.05);超微粉的总酸含量较粗粉显著提高(P<0.05),番茄红素含量较粗粉显著降低(P<0.05),粗脂肪、蛋白质、维生素C含量显著高于细粉与粗粉(P<0.05);3种粉体的灰分含量无显著差异;在粒径减小的同时,超微粉的形状变得规则均匀,超微粉碎未破坏水果番茄的官能团结构、热性质以及分子结构。本研究对水果番茄深加工有一定的指导意义。

响应面法优化方竹笋超微粉制作曲奇饼干的关键配方及品质评价

【目的】探明方竹笋超微制作曲奇饼干的最优配方,为方竹笋深加工提供新思路。【方法】以方竹笋超微粉为主要原料,辅以糖粉、黄油、蛋液等制作方竹笋曲奇饼干,分析感官及外观色泽,确定4个单因素(方竹笋超微粉、糖粉、黄油和蛋液)添加量的优化范围。在单因素试验基础上,采用Design-Expert试验设计进行响应面优化设计,考察方竹笋超微粉、糖粉、黄油和蛋液添加量对方竹笋曲奇饼干感官品质的影响,确定方竹笋曲奇饼干最优配方,并对优化配方的方竹笋曲奇饼干进行理化指标分析。【结果】方竹笋曲奇饼干最佳配方以低筋面粉质量为100%,方竹笋超微粉、黄油、糖粉和蛋液添加量分别为6.00%、55.00%、40.00%和20.00%,烘焙上下火温度150℃,时间20 min。在此条件下制得的方竹笋曲奇饼干,感官审评得分91.50分,具有特殊方竹笋香、口感松脆、甜度适宜、色泽均匀、组织形态良好,饼干中膳食纤维含量达19.16g/100g,蛋白质和脂肪含量分别为4.99 g/100g和27.6 g/100g,过氧化值和酸价分别为0.04 g/100g和0.56 mg/g,符合国家标准《饼干质量通则》(GB/T 20980—2021)要求。【结论】方竹笋曲奇饼干最佳配方应用于方竹笋的精深加工,可使烘焙食品(饼干类)中保留方竹笋的风味和减轻焦化,属于特色产品,各项理化指标均符合国标要求。

双螺杆挤压联合低温冲击磨技术改良大米抛光粉品质

为解决大米抛光粉易酸败变质的问题和改善其理化性质,本文通过双螺杆挤压对大米抛光粉进行稳定化处理,研究不同挤压温度对大米抛光粉储藏稳定性及营养性质的影响;在最佳挤压温度下,进一步利用低温冲击磨在空气分级机不同转速条件下(300、600、1200、1800 r/min)制备不同粒径的大米抛光粉(SR-1、SR-2、SR-3、SR-4),研究空气分级机转速对大米抛光粉挥发性香气化合物及理化性质的影响。结果表明,挤压处理后大米抛光粉的脂肪酶活性从12.94 mg/g显著降低至2.18 mg/g。储藏至第150 d,未经处理的大米抛光粉的脂肪酸值为255.57 mg KOH/100 g,而挤压后样品的脂肪酸值仅为121.90 mg KOH/100 g。挤压处理后,大米抛光粉中膳食纤维、γ-氨基丁酸和γ-谷维素也得到了较好的保留。低温冲击磨可以促进大米抛光粉中挥发性香气化合物的释放,其中SR-3总浓度最高。基于偏最小二乘判别法,根据变量重要性投影值筛选出9个差异标记组分,证实了SR-3风味最浓郁。随着大米抛光粉粒径降低,其比表面积逐渐增大,体积密度呈现逐渐减小的趋势;白度指数从66.08显著增加到76.61;吸水性和溶解性分别从1.77 g/g和24%显著增加到2.37 g/g和31%;傅里叶变换红外光谱分析表明,低温冲击磨处理破坏了淀粉颗粒中的氢键,导致了更多的游离羟基暴露。研究结果可为高品质大米抛光粉加工提供理论依据和技术支撑。

响应面法优化豆渣超微粉煎饼加工工艺研究

以豆渣超微粉和小麦粉等为原料制备煎饼,采用单因素试验和响应面试验研究了豆渣超微粉煎饼加工工艺,选取了豆渣超微粉和小麦粉比例、水的添加量和食盐的添加量三个影响较大的因素,采用响应面法优化了最佳工艺。结果表明,豆渣超微粉煎饼的最佳工艺条件为:豆渣超微粉和小麦粉比例2∶8,水的添加量150%,食盐添加量1.2%。此时感官得分平均值为93.8,与理论值较为接近,说明该模型可靠。

超微粉碎果蔬粉的活性成分、物理特性与食品开发研究进展

超微粉碎是一种新兴的制粉技术,该技术能提高物料利用率、改善食品加工特性、提升产品品质,目前已广泛运用于果蔬加工领域。该文综述了超微粉碎对果蔬粉活性成分包括多酚、多糖、维生素C、蛋白质和矿物质的影响;分析了超微粉碎对果蔬粉物理性质包括粒径、休止角和滑角、溶解度、膨胀力、持水力和阳离子交换能力的影响;另外讨论了果蔬超微粉在面制品、功能食品、乳制品和肉制品开发中的应用,以期为超微粉碎果蔬粉在食品工业中应用提供实践参考。

Effect of Serum from Overfatigue Rats on JNK/c-Jun/HO-1 Pathway in Human Umbilical Vein Endothelial Cells and the Intervening Effect of Tongxinluo(通心络)Superfine Powder

Objective:To cultivate human umbilical vein endothelial cells (HUVECs) in the serum of overfatigue rats with the intervention of Tongxinluo (通心络) superfine powder (TXLSP).By examining the variation of the activity of JNK/c-Jun/HO-1 pathway,the possible mechanisms of vascular endothelial dysfunction under overfatigue conditions and the intervening effect of TXLSP were explored.Methods:The HUVECs were randomly divided into the normal control group,the model group,the SP600125 (a specific antagonist of JNK)gro...

Observation of changes in the number of myocardial capillaries in rabbits after treatment of acute myocardial infarction by Tongxinluo superfine powder

OBJECTIVE: To investigate the effects of Tongxinluo superfine powder on cardiac function, infarct size and the number of myocardial capillaries in a rabbit model of acute myocardial infarction.METHODS: A total of 32 New Zealand white rabbits were randomly divided into four groups: sham operation group, model group, treatment group,and pre-treatment, the experiment of pre-treatment group was performed 6 weeks early than the treat) group,The four groups use a unified modeling technique. An acute myocardial infarction model was established through external application of70% ferric chloride on the coronary artery. After 7 d,electrocardiogram, ultrasonography of cardiac function, micro-computed tomography, pathology and other data were collected.RESULTS: In the treatment and pre-treatment groups, ejection fraction, left ventricular short axis shortening rate, left ventricular end-systolic diameter and cardiac output significantly improved, the number of capillaries significantly increased, and infarct size significantly decreased. In addition, the results suggest that the value of intra-ventricular pressure and the situation of electrocardiogram also changed to different degrees with the increasing of treatment of cycle.CONCLUSION: Tongxinluo superfine powder can protect the myocardium, improve the blood supply of the myocardium and reduce the degree of myocardial injury, during acute stage of myocardial infarction.