Surface energy of preservative-treated southern yellow pine (Pinus spp.) by contact angle measurement     

Jinzhen Cao  Pascal D. Kamdem 《Frontiers of Forestry in China》2007,2(1):99-103

In this study, the contact angles of four different reference liquids (including distilled water, diiodomethane, formadide and glycerol) formed on the surfaces of wood, treated with chromated copper arsenate (CCA) and two other emerging copper-based water-borne systems (commercial names: NW and NS) were measured with sessile drop method. Based on the contact angle data, the surface energy was obtained from the acid-base approach. The total surface energy consisted of Lifshiz-van der Waals parameter and acid-base parameter. Results showed that the NW and CCA treatments made the wood surface more hydrophobic while the NS treatment had the reverse effect on the wood surface mainly owing to the increased penetration of earlywood. By using three liquids, diiodomethane, formamide and distilled water, the total surface energy obtained for untreated earlywood, untreated latewood, CCA-treated earlywood, CCA-treated latewood, NW-treated earlywood, NW-treated latewood, NS-treated earlywood and NS-treated latewood were 43.1, 44.5, 43.4, 45.1, 49.4, 40.6, 46.0 and 40.9 mJ/m², respectively. The surface energy of CCA-treated wood was almost the same as untreated wood. After NW and NS treatments, the surface energy of both earlywood and latewood changed a little. However, the change was not so obvious as to draw any further conclusion concerning the influence of NW and NS treatments on the surface energy of wood. __________ Translated from Journal of Beijing Forestry University, 2006, 28(4): 1–4 [译自: 北京林业大学学报]  相似文献   

非洲菊切花保鲜剂的研究   总被引：15，自引：0，他引：15  

姜霞  熊忠华 《贵州林业科技》2004,32(1):20-26

本文研究由蔗糖、硝酸银、8-HQ(8-羟基喹啉)配制的不同保鲜剂对非洲菊切花插瓶寿命、水分平衡、鲜重变化及观赏值等指标的影响。结果表明：4％蔗糖 200mg／L硝酸银 200mg／L硫酸铝 320mg／L8-HQ的保鲜效果最好。  相似文献   

Supercritical fluid extraction of sapogenins from tubers of Smilax china   总被引：2，自引：0，他引：2  

Shu XS  Gao ZH  Yang XL 《Fitoterapia》2004,75(7-8):656-661

Supercritical CO(2) fluid extraction (SFE-CO(2)) was used to extract the sapogenins after acid hydrolysis from Smilax china tubers. The influence of extraction variables, such as modifier, pressure, temperature and extraction time, were studied. SFE-CO(2) was found to produce higher yield than conventional solvent extraction. The highest yield (0.454%) of sapogenins, mostly containing diosgenin, was obtained using 35 MPa pressure, 65 degrees C and 95% EtOH as a modifier for 180 min, higher than that obtained with conventional extraction methods (0.385%).  相似文献   

天然动植物色素的特性及其提取技术概况   总被引：16，自引：0，他引：16       下载免费PDF全文

郑华  张弘  张忠和 《林业科学研究》2003,16(5):628-635

综述了天然生物色素在动植物体中的分布和特定生理功能。概括了动植物色素的主要提取方法及其发展状况：直接破碎原料、溶剂浸提、物理技术辅助浸提和现代仪器提取分离等;指出超临界流体萃取(SFE)是较具发展潜力的高效萃取方法,有利于提高色素产品质量。  相似文献   

菠萝果皮汁有效成分的研究     

古和平  林文光  邹建云 《热带农业科技》1997,(4)

菠萝果皮鲜汁蛋白酶活性一般在０．０３—０．０６万单位／ｇ，总糖６％—８％，总酸０．３５％—０．６５％，挥发酸０．０２％—０．２０％，ｐＨ值３．５—４．１。夏季有效成分比冬季高。随自然贮存时间延长，酶活性、总糖含量逐渐降低，总酸、挥发酸逐渐升高。尤以总糖变化最大，贮存６ｄ，下降幅度达８２％。保鲜剂对总糖保护有明显效果，对酶活性保护效果略差。  相似文献   

新防腐剂TWP橡胶木防腐试验   总被引：3，自引：0，他引：3  

施振华  谭淑清 《林业科学》1992,28(6):524-531

TWP防腐剂对木腐菌的毒性剂量为2.2—3.2kg/m~3,毒杀双钩异翅长蠹初龄幼虫的剂量为1.0kg/m~3,抑制蓝变菌和霉菌的毒性浓度分别为1％及1.5—2.0％,对雄性小鼠口服半致死剂量(LD_(50))为1301mg/kg,使用时对人、畜和环境比较安全,并保持木材原有色泽。生产性应用试验结果表明,橡胶木生材用2.0—2.5％TWP,满细胞法或振荡加压法处理,净药保持量4±0.7kg/m~3,防腐效果相当干硼酚合剂12kg/m~3,并优于进口防腐剂。  相似文献   

竹提取物抗菌杀虫性能的研究进展   总被引：2，自引：0，他引：2  

龚金炎  吴晓琴  张英 《竹子研究汇刊》2006,25(3):28-30,31

竹子不同部位含有特征性的生物活性成分,将其开发成天然食品防腐剂和杀虫剂已成为当今的研究热点,该文综述了竹叶提取物、竹醋液、竹皮提取物的抑菌、杀虫作用及其相关研究进展,以期为竹子提取物在食品添加剂和生物农药领域的应用提供信息。  相似文献   

Influence of Disease Process and Duration on Acute Phase Proteins in Serum and Peritoneal Fluid of Horses with Colic          下载免费PDF全文

T.H. Pihl  E. Scheepers  M. Sanz  A. Goddard  P. Page  N. Toft  P.H. Andersen  S. Jacobsen 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(2):651-658

Background

The acute phase proteins (APP) serum amyloid A (SAA), haptoglobin, and fibrinogen are valuable blood biomarkers in equine inflammatory diseases, but knowledge of factors influencing their concentrations in blood and peritoneal fluid (PF) of horses with colic is needed.

Objectives

The objective of this study was to investigate the influence of demographics (age, sex, breed), disease process (simple obstruction, strangulating obstruction, inflammatory), disease location, disease duration, hypovolemia, and admission hospital on concentrations of APP, lactate and white blood cell counts (WBC) in horses with colic admitted to 2 referral hospitals.

Animals

The study included 367 horses with colic admitted at 2 referral hospitals.

Methods

Prospective multicenter observational study of clinical data, as well as blood and PF biomarkers. Associations between biomarker concentrations and clinical variables were analyzed using multivariate linear regression analysis.

Results

Increasing pre‐admission duration of colic was associated with increased concentrations of APP in blood and PF. Blood concentrations of SAA and fibrinogen were associated with disease process (inflammatory, strangulations, simple obstructions) in more colic duration groups (5–12 and >24 hours) than any of the other biomarkers. No relevant associations between demographic factors, hospital, or hydration status and the measured biomarkers were found.

Conclusions and Clinical Importance

In horses with colic, concentrations of APP are associated mainly with disease process and duration of colic and may thus be used for assessment of disease independently of demographic or geographic factors. Serum amyloid A may be a diagnostic marker for use in colic differential diagnosis, but further evaluation is needed.  相似文献   

Synovial fluid total protein concentration as a possible marker for canine idiopathic polyarthritis     

Kohei MURAKAMI  Tomohiro YONEZAWA  Naoaki MATSUKI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1715-1717

Idiopathic polyarthritis (IPA) is a very common inflammatory arthropathy in the dog. Canine IPA is diagnosed mainly by detecting increased number of leukocytes in the synovial fluid (SF), which is easily influenced by glucocorticoid therapy. We obtained 31 SF samples from 24 IPA dogs prior to (n=19) and/or after (n=12) 1 to 10 weeks of glucocorticoid therapy. The SF total protein concentrations of IPA dogs were significantly higher than those of dogs with non-arthritis diseases (n=34) and healthy controls (n=10). Our data revealed that the SF total protein concentrations are not influenced by several weeks of glucocorticoid therapy. Hence, the SF total protein concentration is applicable as a diagnostic marker of canine IPA even when the patients are receiving glucocorticoid therapy.  相似文献   

Changes in the predicted function of the rumen bacterial community of Japanese Black beef cattle during the fattening stages according to Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses     

Asahi HORINAKA  Yo-Han KIM  Atsushi KIMURA  Eiji IWAMOTO  Tatsunori MASAKI  Toshihiro ICHIJO  Shigeru SATO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1098

We investigated changes in the predicted functions of the rumen bacterial community in Japanese Black beef cattle during fattening. Nine cattle were fed a high-concentrate diet during the early, middle, and late fattening stages consecutively (10–14, 15–22, and 23–30 months of age, respectively). The rumen fluid and solid samples collected at each stage were subjected to sequencing analyses. The sequencing results were clustered and classified into operational taxonomic units (OTUs). Representative sequences and a raw counting table for each OTU were submitted to the Piphillin website. The predicted functions were revealed by the Kyoto Encyclopedia of Genes and Genomes database as the ratio of the total sequence. In the early stage, “Biosynthesis of secondary metabolites” was significantly higher in the fluid fraction than in the solid fraction. “Two-component system” in the middle stage was significantly lower and “Purine metabolism” in the late stage was significantly higher in the fluid fraction than those in the solid fraction. The fluid fraction was significantly correlated with acetic acid, propionic acid, and bacterial metabolism, such as “Biosynthesis of secondary metabolites” and “Sugar metabolism.” Moreover, the solid fraction was correlated with “Purine metabolism” and “Biosynthesis of secondary metabolism”. These results suggest that the rumen bacterial community in Japanese Black beef cattle adapts to changes in rumen conditions by altering their functions in response to a long-term high-grain diet.  相似文献