儿茶素氧化产物的分离鉴定及其抗氧化活性研究

采用H2O2模拟氧化体系制备儿茶素氧化产物，经多级柱色谱分离得到一相对纯组分（t_R为9．825min），HPLC-MS分析结果表明，所得级分主要含m／z 471及m／z 939两种产物，     

过氧化物预硫化天然胶乳制备的医用天然胶乳制品热氧降解及其动力学分析

使用热重分析法（TGA）研究了空气状态下过氧化物预硫化天然胶乳（PPVL）制备的医用胶乳胶管试样的热氧降解反应过程及其反应动力学。TG—DTG曲线显示,试样氧化降解过程为二步反应,DTG曲线相应出现明显主降解峰和次降解峰,它们失重1％时的温度（To）、降解峰温度（Tp）、终止温度（Tf）均随升温速率（β）的增加而向高温方向偏移,降解速率也随之增大。在第1步降解反应前,试样出现明显的氧化增重现象,增重峰的温度随β的增加而升高,而增重率随β的增大而减少：试样β为5℃／min的增重峰温度187．9℃,增重率1．33％。第1步反应的最大热氧降解率（Cp1）、最终热氧降解率（Cf1）,反应活化能（E）随着β的增加而增加;表观活化能Eo=107．5kJ／mol;不同β的降解反应级数（β）均是1．7,不受β的影响。第2步反应的Cp2和Cf基本上不受β的影响;n随β的大小而不同,但二者无相关关系;E随β的增加而增加,Eo=154．0kJ／mol。第1步反应和第2步反应的频率因子（A）均随β的增加而几乎呈几何级数增加。第1步反应最大相关系数r均在0．999以上,第2步反应的r均在0．982以上。各升温速率试样在600℃降解率为99．2％-99．5％不等。     

豫单998玉米最佳种植密度试验探讨

在一定种植密度范围内．随着密度的增加．产量水平也随之增加．超过一定密度．产量随密度增加而下降，抗逆性也随之下降。试验结果表明．豫单998在6．6万株／hm2时产量最高，株高、穗位、穗长、穗粒数、千粒重等农艺性状比较适宜，抗逆性较强．为豫单998在当地肥力条件下的最佳种植密度。     

H2O2浸种对低温胁迫下花生种子萌发的调控作用

为了研究H2O2浸种对低温胁迫下花生种子萌发的调控作用，本研究以白沙1016和花育9122两个花生品 种为材料，通过种子萌发试验，设置（22±1）℃常温对照和（12±1）℃低温处理，首先采用不同浓度的H2O2进行浸种预 处理，分析了H2O2浸种对花生种子低温萌发相关指标的影响，筛选最适H2O2浸种浓度，然后采用最适H2O2浸种处 理后，测定其对发芽花生种子胚中氧化损伤和活性氧含量、脯氨酸代谢相关指标的影响。结果表明，低温显著降低 两个品种花生的相对发芽率、芽长/种长比、发芽指数及种子的活力指数，延长了平均露白时间，H2O2浸种预处理可 显著缓解低温对花生种子萌发的抑制，以1% H2O2浸种效果最好。同时，H2O2浸种预处理还显著降低了H2O2的积累 以及膜脂过氧化程度，促进了脯氨酸的积累，提高了脯氨酸合成酶鸟氨酸转移酶（OAT）和△1-吡咯琳-5-羧酸合成 酶（P5CS）活性，抑制了脯氨酸降解限速酶脯氨酸脱氢酶（ProDH）活性。表明H2O2浸种预处理可通过调控脯氨酸代 谢途径，促进低温条件下萌发花生种子内脯氨酸的积累，缓解氧化损伤，从而增强花生种子的低温萌发能力。     

黑龙江省高产红麻品种筛选与配套栽培技术研究

本文以国内最新品种在黑龙江双城进行品比试验和配套栽培试验。结果表明：H305杂种麻干茎16222．5kg/hm^2最高，中红麻11号14550．0kg／hm^2居二，7804为14347．5kg／hm^2第三。H305较7804等其他品种增产显著或极显著。播期表明：共同趋势是随播期提早而增产，7804和H305杂种麻于4月底播种比5月初播种，分别增产19．0％、9．0％。肥料与密度试验以每hm^2施N150kg、K2O150kg，产量较高，比高肥区施N225kg、K2O225kg、P2O575kg，增产干茎1410kg／hm^2。     

甜菜碱浸种对干旱条件下裸大麦叶片H2O2代谢的影响

干旱条件下裸大麦叶片H2O2含量增加,ASA-POD和GR活性均表现"先上升后下降"的趋势.叶片ASA与GSH含量均随干旱时间的延长而逐渐下降.抗旱性较强的裸大麦品种白玉紫芒在干旱条件下能维持较强的H2O2清除能力,H2O2累积较少.甜菜碱浸种可以明显抑制干旱过程中H2O2含量增加,在一定程度上阻止ASA-POD与GR活性及ASA和GSH含量的下降,甜菜碱对抗旱性较弱的品种的影响明显大于抗涝性较强的品种.     

花生不同部位对提取DNA的影响

采用CTAB法和SDS法，分别从花生的根尖、下胚轴、种子、幼叶中提取基因组DNA，所提DNA片段长度都在21 kb以上；同种方法中部位之间的DNA纯度没有差异，产率差异极其显著，从种子、根尖、下胚轴到幼叶产率依次升高，CTAB法中产率从128．5～498．5ng／mg，SDS法中产率从225．O～542．6ng／mg；两种方法中，相同部位之间只有叶片在纯度上差异显著，产率上相同部位之间的差异极其显著。用CTAB法从叶片中提取DNA，采用RAPD方法，对19个花生品种的基因组进行扩增，结果显示所提DNA满足分子分析的要求。RAPD可用于亲本和品种的鉴定。     

水稻单粒种子DNA提取及SSR—PCR反应体系的正交设计优化

以水稻单粒干种子为材料．进行了DNA提取方法和SSR-PCR反应体系的优化研究。结果表明：用CTAB法提取的水稻干种子DNA较为完整,降解量少。可获得理想的扩增效果。在试验设计范围内,确定的最佳反应体系为201．11．其中含模板DNA35ng,dNTPs浓度为0．15mm01／L,引物浓度0．41．1m01／L,M矿浓度为1．5mmol／L,Taq酶为1．6U。     

H2O2和NO对反季节龙眼成花及FT基因表达的影响

为阐明H2O2和NO对龙眼成花及FT基因表达的影响，选用9年生‘石硖’反季节龙眼，结合H2O2和NO促进剂及信号阻断剂喷施，分析龙眼成花及FT基因表达量的动态变化。结果表明：反季节龙眼FT基因表达量在成花过程中上升，且叶片中FT基因表达高峰时间早于顶芽，而SNP和MV均不同程度上调了FT基因的表达；DMTU和L-NNA有效地抑制了顶芽中FT基因的表达，但对花芽分化后期的叶片中FT基因表达抑制不明显。结合龙眼成花情况，推断H2O2和NO信号在促进龙眼成花方面具有重要作用。     

茶叶叶绿素锌钠盐的制备及其稳定性研究

利用新鲜茶叶制备叶绿素锌钠盐,研究其最佳锌代工艺条件,并对其稳定性进行研究。结果表明,锌代反应最佳工艺条件为:茶叶粉(g):ZnSO4.7H2O(g)=5:7.1;温度为60℃;时间为2h,收率为2.1%。叶绿素锌钠盐水溶性、耐热性、耐氧化还原性、pH为2.8~12.78时的耐光性均较好,常见的食品添加剂和金属离子对叶绿素锌钠盐的稳定性无影响。     

Mechanical properties of semi-interpenetrating polymer network hydrogels based on poly(2-hydroxyethyl methacrylate) copolymer and chitosan

Semi-interpenetrating polymeric network (semi-IPN) hydrogels based on poly(2-hydroxyethyl methacrylate) (PHEMA) and poly(2-hydroxyethyl methacrylate-co-sodium methacrylate) [P(HEMA-co-SMA)], and chitosan with different molecular weights were prepared by crosslinking with ethylene glycol dimethacrylate (EGDMA) and poly(ethylene glycol) diacrylate (PEGDA) and their gelation time, water content, mechanical properties, and morphology were investigated. In consideration of the influence of the molecular weight of chitosan, there is no big difference in the water content, while tensile properties and compressive modulus increased as the molecular weight of chitosan increased. The water content increased and tensile properties and compressive modulus decreased with increasing SMA concentration. Considering the effect of the crosslinking agent, PEGDA had higher water content and lower tensile and compressive moduli than EGDMA. It is suggested that PHEMA/chitosan and P(HEMA-co-SMA)/chitosan semi-IPN hydrogels with different structures and physical properties can be prepared depending on the molecular weight of chitosan, the copolymerization with SMA, and the crosslinking agent type.     

施磷对膜下滴灌水稻生长发育及产量的影响

在膜下滴灌条件下,以粳稻品种T-43为材料,研究了水溶性磷肥施用量对水稻生长发育及产量的影响。结果表明,在施磷量(P2O5)0~156 kg/hm^2范围内,水稻的株高、叶片数随着施磷量增加而上升;以施磷量130kg/hm^2处理的有效分蘖数、有效穗数、穗长、主茎实粒数、分蘖实粒数、千粒重和产量最高;当施磷量达到156kg/hm^2时,有效分蘖数及产量构成因素则呈下降趋势。说明膜下滴灌水稻水溶性磷肥施用有其适宜值,过量施用不仅低产低效,还可能增加土壤环境污染。     

Effect of foliar application of oligochitosan with different molecular weight on growth promotion and fruit yield enhancement of chili plant

Oligochitosan (OC) is effective biostimulant on growth promotion and elicitation against disease infection for plants. However, the range of OC molecular weight that exhibits the most effective activity is not fully understood and requires further investigation. In this study, OCs with different weight average molecular weight (Mw) were prepared by gamma Co-60 irradiation degradation of chitosan in solution and the effect on growth promotion and enhancement of fruit yield of chili plant (Capsicum frutescens L.) by foliar application of OCs particularly with Mw of 7.8, 5.0, and 2.5 kDa was investigated. Chili plants, cultivated in a greenhouse were sprayed with OC concentration of 50 mg/L for three times. Results indicated that among treatments, OC with 2.5 kDa proved to be the best, which increased the shoot fresh weight by 71.5%, shoot dry weight by 184%, total chlorophyll content by 12%, and fruit fresh weight by 49.8% for the control. Thus, OC with low Mw (2.5 kDa) that can be suitably produced on large scale by gamma Co-60 ray irradiation degradation of chitosan solution is potentially promising to apply as a biostimulant to enhance chili fruit yield significantly.     

Hemostatic,antibacterial and degradable performance of the water-soluble chitosan-coated oxidized regenerated cellulose gauze

In this research, the oxidized regenerated cellulose (ORC) gauze was prepared by oxidation of regenerated cellulose using NO₂/CCl₄, subsequently treated with the dissolved chitosan (CTS) in aqueous acetic acid (CTS/ORC) and finally neutralized with NaOH/C₂H₅OH (CTS/ORC-Na). The hemostatic, antibacterial and degradable properties of treated ORC-based gauze were evaluated. The results of the hemostatic test on rabbit liver and ear-artery injuries showed that the attachment of high molecular weight chitosan to the surface of ORC gauze significantly improved the hemostatic effect of ORC without compromising the antibacterial and degradability of ORC. It is found that the water-soluble CTS/ORC-Na gauze was more suitable as the hemostatic material applied in rabbit liver injury in comparison with in ear-artery injury and it further improved the hemostatic efficacy and enhanced the degradable rate. It is promised that the CTS/ORC gauze and the water-soluble CTS/ORC-Na gauze would be applicable in medical fields such as surgical absorbable hemostats for control bleeding.     

Long-Term Feeding of Chitosan Ameliorates Glucose and Lipid Metabolism in a High-Fructose-Diet-Impaired Rat Model of Glucose Tolerance

This study was designed to investigate the effects of long-term feeding of chitosan on plasma glucose and lipids in rats fed a high-fructose (HF) diet (63.1%). Male Sprague-Dawley rats aged seven weeks were used as experimental animals. Rats were divided into three groups: (1) normal group (normal); (2) HF group; (3) chitosan + HF group (HF + C). The rats were fed the experimental diets and drinking water ad libitum for 21 weeks. The results showed that chitosan (average molecular weight was about 3.8 × 10⁵ Dalton and degree of deacetylation was about 89.8%) significantly decreased body weight, paraepididymal fat mass, and retroperitoneal fat mass weight, but elevated the lipolysis rate in retroperitoneal fats of HF diet-fed rats. Supplementation of chitosan causes a decrease in plasma insulin, tumor necrosis factor (TNF)-α, Interleukin (IL)-6, and leptin, and an increase in plasma adiponectin. The HF diet increased hepatic lipids. However, intake of chitosan reduced the accumulation of hepatic lipids, including total cholesterol (TC) and triglyceride (TG) contents. In addition, chitosan elevated the excretion of fecal lipids in HF diet-fed rats. Furthermore, chitosan significantly decreased plasma TC, low-density lipoprotein cholesterol (LDL-C), very-low-density lipoprotein cholesterol (VLDL-C), the TC/high-density lipoprotein cholesterol (HDL-C) ratio, and increased the HDL-C/(LDL-C + VLDL-C) ratio, but elevated the plasma TG and free fatty acids concentrations in HF diet-fed rats. Plasma angiopoietin-like 4 (ANGPTL4) protein expression was not affected by the HF diet, but it was significantly increased in chitosan-supplemented, HF-diet-fed rats. The high-fructose diet induced an increase in plasma glucose and impaired glucose tolerance, but chitosan supplementation decreased plasma glucose and improved impairment of glucose tolerance and insulin tolerance. Taken together, these results indicate that supplementation with chitosan can improve the impairment of glucose and lipid metabolism in a HF-diet-fed rat model.     

Application of bioactive coatings based on chitosan for artichoke seed protection

Artichoke seeds suffer attacks of various fungi that result in a decreased yield. Coatings based on chitosan were used as an antifungal agent and for enhancing the germination and quality of artichoke seeds. The effect of formulation (chitosan molecular weight, presence or absence of Span 80, pH), and thickness (number of coating layers) on seed germination (G%), fungi activity and vegetative growth were studied. Results indicated significant differences between treatments on seed germination. It was observed that all chitosan treatments reduced the number of type of fungi and increased plant growth. Chitosan with lower Mw gave better results both from microbial and germination point of view. In addition results indicated that treatments including chitosan and TMTD increased significantly G% and plant growth of artichoke seeds and produced a decrease in fungi contamination.     

Effect of various parameters on the chemical grafting of amide monomers to poly(lactic acid)

Radical melt graft copolymerizations of poly (lactic acid) (PLA) with amide monomers using benzoyl peroxide as an initiator during reactive extrusion is studied. The effects of two monomer types at various concentrations, reaction temperatures and initiator concentrations on the grafting yield are investigated. The results showed that percentage of grafting was significantly enhanced by increasing benzoyl peroxide concentrations up to 12 mpm and then decreased by an increase in the initiator concentration. Furthermore, increasing each monomer concentration up to 450 mpm, improved the grafting yield significantly. Further increase brings about a marked fall in the grafting yield. Fourier Transform Infrared Spectroscopy (FTIR), back titration and nitrogen analyses confirmed that monomers of acrylamide and methacrylamide were successfully grafted onto PLA. The Gel Permeation Chromatography (GPC) data showed that the molecular weight of the grafted PLA samples under optimum conditions does not show any dramatic drop of PLA molecular weight by thermal degradation or hydrolysis of polyester chains, while the polydispersity index is poorly affected by the chemical modification of PLA. Also, the monomer structures affected the grafting yield as well as polymer chain combination. In addition under the same conditions, the grafting yield of acrylamide was more than that of methacrylamide. Thermal properties, molecular weight, density, moisture regain and tensile properties of the samples were also measured.     

赣豆4号水旱轮作高产栽培技术研究

研究了不同N、P、K及密度配合，以及化控措施对赣豆4号产量和经济性状的影响。结果表明：处理6（A2B3C1D2)、8（A3B2C1D3）、4（A2B1C2D3）产量最高，分别为2835.84kg/hm^2、2818.08kg/hm^2和2816.28kg/hm^2。密度和K肥对产量影响达极显著水平，N肥影响达显著水平，而P对产量的作用不大。K能促进产量构成因子的形成，提高单株生产力。随着密度增大、N肥用量的增加，株高增加，分枝减少，单株荚数、粒数、单株生产力降低，百粒重减轻。P对促进分枝、提高单株荚数有一定的作用。多效唑、叶面喷肥、钼酸铵拌种、根瘤菌拌种分别比常规种植增产14.39%-5.16%。高产试验平均产量达2673.6-2814.3kg/hm^2，最高产量达3429kg/hm^2，高产示范平均产量2496.5kg/hm^2。     

REGROWTH OF S24 RYEGRASS AND ITS RELATION TO YIELD MEASUREMENT OF GRAZED SWARDS

The re growth of S24 ryegrass (Lolium perenne L.) plants was studied during 4 days, following defoliation to stuhble heights of 2, 4, 6, 8, 10 and 12 cm. The weight of regrowth produced by plants cut to 6-cm stubhie heights and higher was equal to the weight increment of uncut plants above the same heights. During the 4 days the weight of the stubble segment between 0 and 2 cm decreased in plants cut to 2 or 4 cm, but was maintained or increased in plants cut to 6 cm or higher. Weights of the 2- to 4- to 6-cm stubble segments were just maintained at the lower cutting heights, but were increased by the same amount as in uncut plants at the highest cutting height. The percentage of water-soluble carbohydrates in all stubble segments decreased following defoliation, but the percentage of N did not change. Root weights were either maintained or increased, depending on the severity of cutting. In relation to grazing experiments, it is pointed out that where DM disappearance is taken as the difference hetween yield on a protected site and residue on a grazed site, too close cutting of the sample areas will give an overestimate of yield.     

The Effect of Substituent,Degree of Acetylation and Positioning of the Cationic Charge on the Antibacterial Activity of Quaternary Chitosan Derivatives

A series of water-soluble cationic chitosan derivatives were prepared by chemoselective functionalization at the amino group of five different parent chitosans having varying degrees of acetylation and molecular weight. The quaternary moieties were introduced at different alkyl spacer lengths from the polymer backbone (C-0, C-2 and C-6) with the aid of 3,6-di-O-tert-butyldimethylsilyl protection of the chitosan backbone, thus allowing full (100%) substitution of the free amino groups. All of the derivatives were characterized using ¹H-NMR, ¹H-¹H COSY and FT-IR spectroscopy, while molecular weight was determined by GPC. Antibacterial activity was investigated against Gram positive S. aureus and Gram negative E. coli. The relationship between structure and activity/toxicity was defined, considering the effect of the cationic group’s structure and its distance from the polymer backbone, as well as the degree of acetylation within a molecular weight range of 7–23 kDa for the final compounds. The N,N,N-trimethyl chitosan with 100% quaternization showed the highest antibacterial activity with moderate cytotoxicity, while increasing the spacer length reduced the activity. Trimethylammoniumyl quaternary ammonium moieties contributed more to activity than 1-pyridiniumyl moieties. In general, no trend in the antibacterial activity of the compounds with increasing molecular weight or degree of acetylation up to 34% was observed.