水泥植纤比对植纤水泥复合板性能的影响

采用水泥与棉杆、玉米杆、麦秸等植物纤维的不同配比,可研制出植纤水泥复合板。本文主要分析了不同的水泥植纤比对板材的静曲强度、吸水率、厚度膨胀率等的影响,温度对板材线膨胀率的影响,选出较佳的水泥植纤比。该板材是一种理想的新型建筑材料。

一年生植纤复合板

一年生植纤复合板是以一年生植物纤维(如棉杆、麻杆、玉米杆、高粱直、甘蔗渣、麦秸、稻壳、向日葵杆、芦苇、竹、蒲草、椰子壳、茅草和废纸等)为增强材料,以脲醛树脂为粘合剂,经热压而成。特别是对像棉杆皮绒很多的秸杆均能全株利用,节省原材料极其显著,已获国家发明专利。

Analysis on the Production Advantages of USA Pima Extra Long Staple Cotton

This paper defines the following advantages of ELS （Extra Long Staple） also known as Pima cotton planted in the United States： first, the only variety which is concentrated in the planting area with good soil moisture and fertilizer retention performances and abundant light and heat resources; second; advanced and practi- cal material equipment and technology; third; high yield and good quality, significant planting scale benefit; fourth, feasible and reliable modernized intensive farm man- agement mode with large-scale agricultural machinery operation; fifth, high-efficient social services and policy support system, as well as reasonable planting layout, good brand influence, synchronization of high yield and good quality with large-scale benefits. Although the production capability of Pima cotton in the United States is considered to be the largest and most powerful country in the world, compared with the ELS production in China, both have their own advantages and characteristics. Therefore, it is suggested that by using the ELS production experience ol the Unit- ed Stages for reference, China should make use of the modern breeding technJques to accelerate the modification of synthetic genetic features of ELS variety, try its best to breed the ELS variety which is suitable for mechanical plucking as soon as possible, actively develop new technology to simplify the whole cost saving cultiva- tion, reform ELS production organization, vigorously develop the social service sys- tem, and adjust and optimize the ELS industry support policies, so as to fundamen- tally improve the competitiveness of China＇s ELS in international market.

Effect of Plant Fiber-Polyacrylamide Blend on Retention and Evaporation Water at Arid and Semi-Arid Soils of Algeria

Soil and water conservation is essential for sustaining food production and for preserving the environment in arid and semi arid lands （ASALs） where conditions for agriculture and other land use systems are often harsh and unpredictable. The ASALs of Algeria are an important source of a variety of non wood forest products like Stipa tenacissima L. plant （esparto grass）. This research was conducted to determine the effects of different low concentration （〈 I%） polyacrylaJnide, Stipa tenacissima L. fiber （esparto grass fibers） and its mixtures with the polymer at water retention in arid and semi arid soil. All samples are characterized by infrared spectroscopy, X-ray Diffractometry, thermal analysis TG DSC and scanning electron micrographs （SEM）. The results showed that polymer blend in soil could improve better soil physical proprieties decreased evaporation and increase water retention in arid soils compared with application of any other blend at the same concentration. The use of Polyacrylamide-Cellulose blend appears to promise for reducing the labor cost of irrigation at arid and semi-arid soils, and offers safe and environmentally friendly inexpensive materials. The importance of Polyacrylamide-Cellulose blends to alleviate poor physical properties and retain water in these arid regions to sustain plant growth.

Enhanced apoptosis in post-liver transplant hepatitis C:Effects of virus and immunosuppressants

Hepatitis C(HCV)-infected patients have a poorer survival post-liver transplantation compared to patients transplanted for other indications,since HCV recurrence post-transplant is universal and commonly follows an aggressive course.There is increasing evidence that in the non-transplant setting,induction of hepatocyte apoptosis is one of the main mechanisms by which HCV drives liver inflammation and fibrosis,and that HCV proteins directly promote apoptosis.Recent studies have shown that post-liver transplant,there is a link between high levels of HCV replication,enhanced hepatocyte apoptosis and the subsequent development of rapidly progressive liver fibrosis.Although the responsible mechanisms remain unclear,it is likely that immunosuppressive drugs play an important role.It is well known that immunosuppressants impair immune control of HCV,thereby allowing increased viral replication.However there is also evidence that immunosuppressants may directly induce apoptosis and this may be facilitated by the presence of high levels of HCV replication.Thus HCV and immunosuppressants may synergistically interact to further enhance apoptosis and drive more rapid fibrosis.These findings suggest that modulation of apoptosis within the liver either by changing immunosuppressive therapy or the use of apoptosis inhibitors may help prevent fibrosis progression in patients with post-transplant HCV disease.

Research of Degumming Process, Microstructure and Properties of Mulberry Fiber

More and more novel nature fibers are used in textiles. The natural fibers include banana fiber, pineapple fiber and bamboo fiber etc. In this paper, as a kind of novel natural fiber, mulberry fiber is studied. The chemical component of mulberry bast is tested and analyzed. Meanwhile, the degumming method and process of mulberry bast are studied. Chemical degumming experiments to investigate the influence of alkali concentration, alkali boiling time and sodium phosphate tribasic ratio to material are conducted. Consequently, optimum parameters are obtained. The crystallinity of mulberry fiber is tested by using X-ray line, and the photos of scanning electron microscope （SEM） are observed. Testing results of the fiber properties （e. g. fineness, tenacity, length and elongation） show that mulberry fiber can be spun blend with cotton.

Effects of Guiyuanfang and autologous transplantation of bone marrow stem cells on rats with liver fibrosis

AIM: To investigate the therapeutic effects of Guiyuanfang and bone marrow stem cells (BMSCs) on rats with liver fibrosis.METHODS: Liver fibrosis model was induced by carbon tetrachloride, ethanol, high lipid and assessed biochemically and histologically. Liver function and hydroxyproline contents of liver tissue were determined.Serum hyaluronic acid (HA) level and procollagen Ⅲ level were performed by radioimmunoassay. The VG staining was used to evaluate the collagen deposit in the liver.Immunohistochemical SABC methods were used to detect transplanted BMSCs and expression of urokinase plasminogen activator (uPA).RESULTS: Serum transaminase level and liver fibrosis in rats were markedly reduced by Guiyuanfang and BMSCs. HA level and procollagen Ⅲ level were also reduced obviously,compared to model rats (HA: 47.18±10.97 ng/mL,48.96±14.79 ng/mL; PCⅢ: 22.48±5.46 ng/mL, 26.90±3.35ng/mL; P＜0.05).Hydroxyproline contents of liver tissue in both BMSCs group and Guiyuanfang group were far lower than that of model group (1 227.2±43.1 μg/g liver tissue, 1390.8±156.3 μg/g liver tissue; P＜0.01). After treatment fibrosis scores were also reduced. Both Guiyuanfang and BMSCs could increase the expression of uPA. The transplanted BMSCs could engraft, survive, and proliferate in the liver.CONCLUSION: Guiyuanfang protects against liver fibrosis.Transplanted BMSCs may engraft, survive, and proliferate in the fibrosis livers indefinitely. Guiyuanfang may synergize with BMSCs to improve recovery from liver fibrosis.

Research on the Structure and Properties of Mulberry Fiber

The chemical ingredients, morphological structure and properties of mulberry fiber have been researched. The results show that the mulberry fiber is cellulose fiber. The crystal structure of mulberry fiber is cellulose I and the crystal cell belongs to the monoelinic system. The mulberry fiber crystal degree is 62.9% and orientation degree is 43.7%, the fineness of mulberry fiber is 2.3- 3.9 dtex, the length of the single fiber is 28 - 47 mm, the breaking strength of mulberry fiber is about 2.93 cN/dtex, and the initial modulus is about 76.82 cN/dtex.

Effect of maleic anhydride grafted styrene-ethylene-butylene-styrene （MA-SEBS） on impact fracture behavior of polypropylene / wood fiber composites

MA-SEBS as compatibilizer and impact modifier was incorporated into Polypropylene/Wood Fiber （PP/WF） to enhance interface adhesion and impact strength of the composite. The effect of MA-SEBS content on the impact fracture behavior of PP/WF composites was studied. The impact properties of composites with 8% MA-SEBS reached the maximum value. And further increasing of MA-SEBS content to 10% did not improve the fracture toughness, but improved the stiffness of composites by DMA analysis. This was attributed to the improved PP/WF adhesion. As the MA-SEBS content is more than 8%, the molecule interaction of PP and WF was expected to much stronger than lower MA-SEBS. Scanning electron microscopy （SEM） was performed to analyze the impact fracture surface and showed a stronger affinity for the wood surfaces.

Optical interconnection on PCB level using MT compatible connectors and fiber-embedded boards

Optical interconnection between LSIC （Large Scale Integrated circuit） is an increasing demand as data communication is growing very fast, whereas electronic interconnection could hardly satisfy the fastgrowing request of data rate. A realization of on-board optical connection is described in this paper,of which multimode fibers were buried into the RF4 board by cutting grooves on the surface of the board with a LPKF ProtoMat95sll, and two MT connectors were reconstructed to form an input-and-output couple in the board. Optical transmission at 2.5 Gbit/s× 12 channels data rate was demonstrated and a widely opening eye pattern was achieved. Large scale prototype of dense-multimode-fiber-embeddad board for the backplane aoolication was also fabricated by using the methods mentioned in this oaeer.

Effects of salvia miltiorrhiza bge on myocardial fibrosis in hypertensive rats

Objective: To study the effects of Salvia Miltiorrhiza Bge (SMB) on myocardial fibrosis in hypertension in rats. Methods: Normal Wistar kyoto rats served as negative control (group A) . The rats with hypertension were divided into 2 groups: the hypertension group (group B) which served as the positive control and the SMB-treated hypertension group (group C). The effects of SMB on the systolic pressure, the myocardial content of aldosterone (ALD) and nitric oxide (NO) and the activity of superoxide dismutase (SOD) in the myocardium were detected. Results: The systolic pressure of the rats of group C showed no marked change after the administration of SMB and showed no difference from that of the rats of group B. The content of collagen Ⅰ and Ⅲ of the left ventricle, the collagen Ⅰ /collagen Ⅲ ratio and the content-of ALD were lower in group C than in group B and higher in group C than in group A. The content of NO and the activity of SOD in the myocardium were higher in group C than in group B and lower in group C than in group A. Conclusion: It was concluded that SMB was able to prevent or reverse the progress of myocardial fibrosis resulting from hypertension. The mechanism of this effect of SMB might be due to the fact that SMB can decrease the collagen synthesis and ALD content and increase collagen decomposition, NO content and SOD activity in the myocardium.

Contribution of mononuclear bone marrow cells to carbon tetrachloride-induced liver fibrosis in rats

AIM： To study the inhibitory effect of mononuclear bone marrow cell （BNC） transplantation on carbon tetrachloride （CCl4） -induced liver fibrosis in rats. METHODS： Rat liver fibrosis models were induced by CCl4 and alcohol administration. After 8 wk, twenty rats were randomly allocated into treatment group （n = 10） and control group （n = 10）. BMC were infused into the rats in treatment group via the portal vein, while heparinized saline was infused in control group. CCl4 was hypodermically injected into the rats twice a week for 4 wk. At the end of wk 12, all rats were humanely sacrificed. Uver samples were taken and stained with HE or Masson trichrome. The general conditions, liver fibrosis （hydroxyproline and collagen fibre） and liver pathological grades in rats were evaluated. RESULTS： The general conditions of the rats in treatment group improved markedly, but not in control group. Hydroxyproline was 504.6± 128.8 μg/g in treatment group, and 596.0 ± 341.8 μg/g in control group. The percentage of collagen fibre was 3.75% ± 0.98% in treatment group and 5.02% ± 0.44% in control group. There was a significant difference between the two groups （P 〈 0.05）. Liver pathological grade decreased from grade N to grade 11 partially in treatment group （P 〈 0.05） with no obvious improvement in control group （P 〉 0.05）. There was a significant difference between treatment group and control group （P 〈 0.05）.CONCLUSION： Transplantation of BMC can improve liver fibrosis due to chronic liver injury in rats.

Physical Properties and Heat Transfer of Tectona grandis L.f. Wood

Tectona grandis L.f. （teak） is native to the Indian subcontinent and southeast Asia, and today is grown in almost every tropical region, for the physical and mechanical properties of its wood. Also, important qualitative aspects render it one of the most expensive wood species in the world. This work presents a study about the physical properties and heat transfer of T. grandis wood from plantations in C.ceres, Mato Grosso, Brazil. Six trees planted at three different intervals were used--two from each planting density--selected at random and with good phytosanitary characteristics, as well as having representative diameters and heights. The following properties were determined： basic and apparent densities, volume contraction, heat transfer and fiber saturation point. The basic and apparent mean general density of the samples was 0.48 g/cm3 and 0.55 g/cm3, respectively. The mean volume contraction of the teak wood was 8.57%. With decreased levels of wood humidity, loss of volume and planting effects were not significant at 5% probability. Mean heat transfer was 7.3 h/cm and the wood fiber saturation point was 17.25%, below the range found in literature, and there was no influence of the planting density on this property. According to the results, it was concluded that planting density significantly influenced the base density of the wood; the same effect does not occur for the other physical properties, and with respect to heat transfer, the wood was considered difficult to dry.

Osteogenic composite nanocoating based on nanohydroxyapatite, strontium ranelate and polycaprolactone for titanium implants

Titanium and its alloys are commonly used as dental and bone implant materials.Biomimetic coating of titanium surfaces could improve their osteoinductive properties.In this work,we have developed a novel osteogenic composite nanocoating for titanium surfaces,which provides a natural environment for facilitating adhesion,proliferation,and osteogenic differentiation of bone marrow mesenchymal stem cells(MSCs).Electrospinning was used to produce composite nanofiber coatings based on polycaprolactone(PCL),nano-hydroxyapatite(nHAp)and strontium ranelate(SrRan).Thus,four types of coatings,i.e.,PCL,PCL/nHAp,PCL/SrRan,and PCL/nHAp/SrRan,were applied on titanium surfaces.To assess chemical,morphological and biological properties of the developed coatings,EDS,FTIR,XRD,XRF,SEM,AFM,in-vitro cytotoxicity and in-vitro hemocompatibility analyses were performed.Our findings have revealed that the composite nanocoatings were both cytocompatible and hemocompatible;thus PCL/HAp/SrRan composite nanofiber coating led to the highest cell viability.Osteogenic culture of MSCs on the nanocoatings led to the osteogenic differentiation of stem cells,confirmed by alkaline phosphatase activity and mineralization measurements.The findings support the notion that the proposed composite nanocoatings have the potential to promote new bone formation and enhance bone-implant integration.

Phylogenetic studies of four species of ciliate inferred from 16s-like small subunit rRNA gene sequences

The phylogenetic relationships of four ciliate genera （Urostyla, Euplotes, Stylonychia and Pseudokeronopsis）, which also are the important environment inspection species, were analyzed by the comparison of small subunit ribosomal RNA gene sequences. Euplotes appeared as an early branching group whose divergence from the hypotrichous line at a deep level was strongly supported by parsimony and matrix analyses. The analyses also supported the hypothesis that there were closely relationship between species in Urostyla and Holosticha. The sibling species Stylonychia mytilus and S. lemnae could be separated by the evolutionary analyses. Furthermore, Pseudokeronopsis rubra had relatively more closely relationship with the species in Holostichidae than that in Urostylidae based on the evolutionary distance value.

Effect of nitrogen to phosphorus ratios on cell proliferation in marine micro algae

The ratio of nitrogen/phosphorus （N/P） is known to affect cell proliferation of some marine micro algae. We evaluated the effect of N/P ratios on the proliferation and succession of phytoplankton using five marine micro algae species. We used two sources of nitrogen, NH4Cl （N1） and urea （N2）, and a single source of phosphorous, NaH2PO4（P）. The optimal N/P ratio that differed among the five species was affected by the source of nitrogen, being as follows （N1/P, N2/P in order）： Thalassiosira sp. （30/1, 20/1）, Heterosigma akashiwo （30/1, 30/1）, Chroornonas salina （20/1, 30/1）, Chaetoceros gracilis （40/1, 60/1）, and A lexandrium sp. （10/1, 30/1）. Thus, the source of nitrogen must be considered when analyzing the N/P ratio. Our results provide insight for predicting phytoplankton succession in coastal waters and may be used to forecast the potential risk of harmful algal blooms.

EXPERIMENTAL STUDY OF NERVE GRAFT WITH VASCULAR IMPLANTATION

Objective To study the performance of free nerve graft with vascular implantation Material and method Three groups of rats were used A 10 mm nerve defect was made in the sciatic nerve It was repaired respectively with vascularised nerve graft(VNG), free nerve graft with vascular implantation(NGV) or free nerve graft(NG) Before 30 days the revascularisation of the nerve graft was assessed;at 2 to 3 month regeneration of nerve was evaluated Histochemical staining, vascular morphology and electrophysiological examination were undertaken Result and conclusion The number of regenerated blood vessels in VNG and NGV was significantly increased than that in NG before 30 days The ratio of regenerated nerve fiber area and conduction velocity in the first two groups were much better than those in NG at 2 to 3 months

Excess body weight, liver steatosis, and early fibrosis progression due to hepatitis C recurrence after liver transplantation

AIM: To investigate how weight gain after OLT affects the speed of fibrosis progression (SFP) during recurrent hepatitis C virus (HCV) infection of the graft.METHODS: Ninety consecutive patients (63 males,median age 53 years; 55 with HCV-related liver disease),transplanted at a single institution, were studied. All were followed for at least 2 years after OLT and had at least one follow-up graft biopsy, performed not earlier than 1 year after the transplant operation. For each biopsy, a single,experienced pathologist gave an estimate of both the staging according to Ishak and the degree of hepatic steatosis.The SFP was quantified in fibrosis units/month (FU/mo).The lipid metabolism status of patients was summarized by the plasma triglycerides/cholesterol (T/C) ratio. Body mass index (BMI) was measured before OLT, and 1 and 2 years after it.RESULTS: In the HCV positive group, the highest SFP was observed in the first post-OLT year. At that time point,a SFP ≤0.100 FU/mo was observed more frequently among recipients who had received their graft from a young donor and had a pre-transplant BMI value ＞26.0 kg/m2. At completion of the first post-transplant year, a BMI value ＞26.5 kg/m2 was associated with a T/C ratio ≤1. The proportion of patients with SFP ＞0.100 FU/mo descended in the following order: female recipients with a high T/C ratio, male recipients with high T/C ratio, and recipients of either gender with low T/C ratio. Hepatic steatosis was observed more frequently in recipients who, in the first post-transplant year, had increased their BMI ≥1.5 kg/m2 in comparison to the pre-transplant value. Hepatic steatosis was inversely associated with the staging score.CONCLUSION: Among HCV positive recipients, excessweight gain post-OLT does not represent a factor favoring early liver fibrosis development and might even be protective against it.