The Production of Organic-Inorganic Compound Film-Coated Urea and the Characteristics of Its Nutrient Release

The effect of different concentrations of natural macromolecular compound on the characteristics of nutrient release in the membrane materials of organic-inorganic compound film-coated urea was discussed, and the optimal concentrations for better nutrient release was proposed. The characteristics of nutrient release of film-coated urea were evaluated by soil column leaching experiment. Organic-inorganic compound film-coated urea showed good characteristics of nutrient release, which could be well simulated by Logistic curve. The two parameters in this curve, a and r, can be used to present nutrient release of film-coated urea, and followed the order of B 〉 C 〉 A and C 〈 B 〈 A, respectively, indicating that the release was stronger with the increasing concentration of natural macromolecular compound in the membrane, which implied better controllability of nutrient release. The concentration of 5% of natural macromolecular compound showed better characteristic of nutrient release and can be utilized as a membrane material combined with inorganic mineral powders to develop film-coated slow-release fertilizer.

Preparation of Eri silk fibroin and gelatin blend film loaded chlorhexidine using as model for hydrophilic drug release

The objective of this research was to prepare Eri silk fibroin solution for preparing silk film loaded chlorhexidine drug as model for hydrophilic drug release. The Eri silk cocoons were boiled in 0.5%NaCO3 solution at 90℃, and then left in air dried at room temperature. The fibroin was dissolved in 9M (Ca(NO3)2) with ethanol (2 by mole) and heated at 70℃. The silk fibroin (SF) solution was then dialyzed to exclude salt in phosphate buffer. The SF and gelatin (G) solutions were mixed for preparation of films in both with and without chlorhexidine. The films were observed their morphology under scanning electron microscope. The results found that all of films were rough of their surfaces, homogeneous texture without phase separation. The native SF film composed of pores throughout the film area but did not observe in native G film. The results also showed that the SF and G can be good interacted to form hydrogen bonds. These were indicated from FTIR spectra and thermal analysis. The chlorhexidine drug has not affect on the changes of film properties. However, the releasing pattern of chlorhexidine from each film was varied. The highest rate of drug releasing was found in the native SF film while the native G film was the lowest. It might be suggested that the drug releasing rate was depended on polarity of each polymer components.

Influence of Glutaraldehyde on the Properties and Release Kinetic of α-Tocopherol from Chitosan-based Film

A crosslinked chitosan film with α-tocopherol was produced by a solution casting method. The appearance, mechanical properties, morphology, barrier properties and release kinetics of the α-tocopherol were evaluated. The addition of glutaraldehyde and α-tocopherol decreased the lightness and greenness and increased the yellowness of the chitosan-based film. Moreover, it also affected the compatibility of the film due to a decrease in the opacity values. The elongation at break(EB) and tensile strength(TS) values of the film decreased when the glutaraldehyde and α-tocopherol were added. In contrast, the Young’s modulus(YM) values increased. SEM micrographs showed coarse spots and pores on the surface and cross-section of the film when compared with the chitosan film. Based on the results, it was indicated that the chitosan structure was disconnected by the α-tocopherol, and the glutaraldehyde as a crosslinking agent generated a link between the chitosan network, which could be the cause of the reduced flexibility and the increased surface roughness of the film. However, the glutaraldehyde and α-tocopherol did not result in a significant difference in water vapour permeability(WVP) values. The glutaraldehyde influenced the release kinetics of the α-tocopherol as seen by the decrease of the diffusion coefficient values that were calculated using the Fickian diffusion model.

Anastomotic stoma coated with chitosan film as a betamethasone dipropionate carrier for peripheral nerve regeneration

Scar hyperplasia at the suture site is an important reason for hindering the repair effect of peripheral nerve injury anastomosis. To address this issue, two repair methods are often used. Biological agents are used to block nerve sutures and the surrounding tissue to achieve phys- ical anti-adhesion effects. Another agent is glucocorticosteroid, which can prevent scar growth by inhibiting inflammation. However, the overall effect of promoting regeneration of the injured nerve is not satisfactory. In this regard, we envision that these two methods can be combined and lead to shared understanding for achieving improved nerve repair. In this study, the right tibial nerve was transected 1 cm above the knee to establish a rat tibial nerve injury model. The incision was directly sutured after nerve transection. The anastomotic stoma was coated with 0.5 × 0.5 cm^2 chitosan sheets with betamethasone dipropionate. At 12 weeks after injury, compared with the con- trol and poly （D, L-lactic acid） groups, chitosan-betamethasone dipropionate film slowly degraded with the shape of the membrane still intact. Further, scar hyperplasia and the degree of adhesion at anastomotic stoma were obviously reduced, while the regenerated nerve fiber structure was complete and arranged in a good order in model rats. Electrophysiological study showed enhanced compound muscle action potential. Our results confirm that chitosan-betamethasone dipropionate film can effectively prevent local scar hyperplasia after tibial nerve repair and promote nerve regeneration.

Effect of backing films on the transdermal delivery of cyclobenzaprine patch

The aim of this study was to investigate the effect of backing films on transdermal delivery of cyclobenzaprine patch. Different backing films were chosen to prepare the cyclobenzaprine transdermal patch. The cumulative amount of cyclobenzaprine released from different patches was evaluated in vitro. To investigate the interaction between cyclobenzaprine and backing films, the partitioning experiments and attenuated total reflectance Fourier transform infrared(ATR-FTIR) spectroscopy were performed. The cumulative amount of cyclobenzaprine released from the patch with Cotran? 9700 as backing film was less than that of other patches with different backing films. Furthermore, the cumulative amount of cyclobenzaprine released from the patch with Cotran? 9700 as backing film decreased significantly after 7 d storage at room condition. The partitioning experiments indicated a strong adsorption of cyclobenzaprine onto the Cotran? 9700, which could explain the decrease of cumulative amount of cyclobenzaprine released from the patch with Cotran? 9700 as backing film. According to the ATR-FTIR results, there was no interaction between Cotran? 9700 and cyclobenzaprine. The effect of backing films on the release behavior of cyclobenzaprine transdermal patch was attributed to the adsorption of cyclobenzaprine onto the Cotran? 9700.

空间的焦虑与释放——新力量导演创作的一种观察

近年来“中国电影新力量”导演声势渐显,他们关注社会问题,常取用当代都市作为空间情境,并以对空间的观察反映当下的现实与焦虑。在他们的电影创作中,空间有着典型的现代症候,如空间中人与人之间的疏离,空间中时间的紊乱,以及空间的功能性失位。这些空间的焦虑是某种社会心理发生改变的症候,而通过影像对现实的针砭与对边缘群体的关怀则是新力量导演们释放焦虑的方法。

白屈菜总生物碱缓释片制备工艺研究

目的:以羟丙基甲基纤维素为缓释材料制备白屈菜总生物碱缓释薄膜衣片解决白屈菜有效成分药物浓度不稳定的缺点,并建立可靠的含量测定方法。方法:采用单因素实验对白屈菜总碱缓释薄膜衣片制备工艺进行筛选,以释放度为依据;采用高效液相色谱法(HPLC)建立了白屈菜总碱缓释薄膜衣片中血根碱的含量测定方法。结果:优化的缓释片工艺处方:30%白屈菜总碱提取物、30%HPMC、20%可压性淀粉、10%乳糖、10%微晶纤维素,挤压制粒,加1%硬脂酸镁,压片,即得。结论:该工艺制得白屈菜总碱缓释片释药曲线平缓,缓释效果良好,方法简单易行,所得薄膜衣片外观和可压性良好。

马铃薯淀粉膜制备工艺优化及活性包装中百里香酚释放动力学

为提高食品包装中抑菌剂百里香酚(thymol,THY)的生物利用率以延长食品的货架期,该研究采用介孔二氧化硅(mobil composition of matter No. 41,MCM-41)作为THY的控释载体(THY-MCM-41),以马铃薯淀粉为原料制备马铃薯淀粉活性包装膜。利用L_(9)(3^(4))正交试验探究马铃薯淀粉、甘油、氯化钙和THY-MCM-41质量浓度对包装膜机械、物理以及水蒸气阻隔性能的交互影响,优化马铃薯淀粉活性包装膜最佳制备工艺参数,并在不同储存环境下对最优组合活性包装膜中百里香酚的释放动力学进行研究,构建百里香酚释放预测模型。结果表明,当马铃薯淀粉质量浓度为0.04 g/mL,甘油质量浓度为0.015 g/mL,氯化钙质量浓度为0.005 g/mL,THY-MCM-41质量浓度为0.005 g/mL时,制备的包装膜A综合性能最优,其抗拉强度、溶胀度、水蒸气透过率、透氧性和不透明度分别为7.16 MPa、89.23%、1.42×10^(-10)g/(m·s·Pa)、1.02×10^(-15)cm^(2)/(s·Pa)和1.16 mm^(-1)。电子扫描电镜和傅里叶红外光谱分析均证实了THY-MCM-41均匀地分散在马铃薯淀粉膜中,与马铃薯淀粉之间具有良好的相容性。马铃薯淀粉活性包装膜可控制百里香酚的释放速率,将百里香酚的有效作用时间延长到10 d。其中,百里香酚的释放规律符合一级释放模型(R^(2)> 0.980),其释放行为遵循菲克扩散定律。该研究为智能活性包装膜中活性物质的精准控释提供了理论基础。

长期覆膜旱作和施用包膜尿素对水稻产量、氮肥利用率及土壤养分的影响

水稻覆膜旱作栽培(non-flooding plastic film mulching cultivation,PM)是以地膜覆盖为核心来实现水稻节水生产的综合集成创新技术。然而,在覆盖地膜后,氮肥只能在移栽前作为基肥一次性施用,导致水稻前期营养生长过盛和生育后期潜在缺氮,从而限制了水稻高产。聚合物包膜尿素(polymer coated urea,CR)是一种控释氮肥,在传统淹水栽培(traditional flooding cultivation,TF)模式下已成为提高作物产量和氮肥利用率的最佳管理措施之一,但尚未在PM模式下进行长期定位试验评估。本研究以高产中熟籼型杂交稻‘两优培九’为供试水稻品种,比较在PM和TF 2种栽培模式下施用CR和普通尿素(urea,UR)对水稻产量、氮肥利用率及土壤养分含量的影响。结果表明:与UR相比,在TF和PM模式下施用CR使水稻氮肥利用率分别提高9.2%和15.4%(P<0.05),使水稻产量分别提高8.6%和15.0%(P<0.05)。与TF模式相比,PM模式加速了土壤有机质的分解,降低了土壤全氮、碱解氮含量。与施用UR相比,在PM模式下施用CR能缓解土壤全氮、碱解氮含量的下降,并使经济效益提高16.8%。综上所述,施用CR是解决在PM模式下水稻生育后期缺氮问题的有效途径。

酸刻蚀埃洛石纳米管/丁香精油混合负载物对PBAT/PPC复合薄膜性能的影响

为探究丁香精油和酸刻蚀埃洛石纳米管(halloysite nanotubes,HNTs)/丁香精油混合负载物(HNTs-4Mclove)对PBAT/PPC复合薄膜性能的影响,首先对HNTs进行酸刻蚀处理,然后将丁香精油与酸刻蚀HNTs负载混合,得到HNTs-4M-clove。丁香精油和HNTs/丁香精油混合负载物的加入使薄膜呈现黄绿色,薄膜的透明性和气体阻隔性略有下降,但对大肠杆菌、金黄色葡萄球菌和腐败希瓦氏菌展现出良好的抗菌性。相较于仅添加丁香精油的薄膜,含HNTs/丁香精油的薄膜在抗拉强度和气体阻隔性方面有所提升。同时,HNTs有助于丁香精油在薄膜中的分散,在一定程度上减缓了丁香精油的释放。因此,酸刻蚀HNTs/丁香精油混合负载物不仅赋予PBAT/PPC薄膜良好的抗菌性,还可减缓薄膜中丁香精油的释放,为可降解缓释型活性包装薄膜的开发提供了参考。

薄荷精油乳液载量对凝胶膜制备及其缓释性能的影响

本文通过高压均质法制备了β-环糊精稳定的薄荷精油Pickering乳液,将该乳液加入壳聚糖溶液流延制备负载精油的凝胶膜,研究薄荷精油载量对凝胶膜性能的影响。结果表明,环糊精稳定薄荷精油Pickering乳液由油滴堆积于外水相而成,粒径89 nm、Zeta电位-32.5mV,对外界振荡有很好稳定性。将乳液加入壳聚糖溶液制膜,油滴分散度良好,无油析现象发生。随着薄荷精油载量的增加,凝胶膜透明度下降、黄色色度增加,膜吸湿性和水蒸气透过性有不同程度降低;薄荷精油乳液的添加可显著提高凝胶膜的拉伸强度,但柔韧性有所下降;顶空浓度测定表明负载薄荷精油的凝胶膜具有缓释薄荷精油的特性。

琥珀酸美托洛尔缓释微丸保护性衣层对其缓释片形成的影响与初步评价

目的评价羟丙纤维素及羟丙甲纤维素对琥珀酸美托洛尔缓释微丸的机械保护作用及差异。方法用不同分子量等级的羟丙纤维素和羟丙甲纤维素对琥珀酸美托洛尔缓释微丸进行包衣,通过检测微丸负压载荷、微丸完整性、体外溶出曲线,评价两种高分子材料对微丸的保护效果。通过制备了羟丙纤维素和羟丙甲纤维素薄膜并考察两种高分子材料薄膜的抗张强度、延展率、韧性和弹性模量等方面的机械性能差异。结果包被羟丙纤维素和羟丙甲纤维素的琥珀酸美托洛尔微丸,断裂载荷增加,压片后微丸完整性提高,机械性能提升,药物泄漏率降低。结论羟丙纤维素和羟丙甲纤维素保护层包衣对琥珀酸美托洛尔片释放单元有一定的机械保护作用,羟丙纤维素具有相对更高的保护能力,可以为多单元微丸药物释放系统的微丸保护策略提供借鉴。

Physicochemical properties,antimicrobial activity and oil release of fish gelatin films incorporated with cinnamon essential oil

Fish skin gelatin films incorporated with various concentrations of cinnamon essential oil(CEO)were prepared and characterized.The results showed that tensile strength(TS),elongation at break(EAB),and water content(WC)of the gelatin based film decreased with the increasing concentrations of CEO,but water vapor permeability(WVP)increased.Addition of CEO improved light barrier property of the film.The Scanning electron microscope(SEM)showed that the heterogeneous surface and porous formation appeared in gelatin-CEO films.Fourier transform infrared spectroscopy analyses(FTIR-ATR)spectra indicated the interactions existed between gelatin and CEO.The gelatin-CEO films exhibited good inhibitory effects against the tested microorganisms(Escherichia coli,Staphylococcus aureus,Aspergillus niger,Rhizopus oryzae,and Paecilomyces varioti)and their antifungal activity seemed to be more effective than the resistance to bacterial growth.In vitro release studies showed an initial burst effect of CEO release and that subsequently slowed down at 40℃,but the initial burst release was not obvious at 4℃.The obtained results suggested that incorporation of CEO as a natural antimicrobial agent into gelatin film has potential for developing as active food packaging.

基于专利数据的包膜缓/控释肥料技术发展态势与我国发展对策研究

缓/控释肥料是减少农业碳排放的重要手段之一。本文以专利数据为基础,对包膜缓/控释肥料的全球专利申请态势进行分析,归纳总结了各技术分支的申请量、国外专利申请区域、全球主要申请人,并梳理了全球专利技术功效和主要技术发展脉络,旨在通过对现有技术的梳理规整,明晰技术发展现状和发展路线,以期对国内申请的技术研发和专利布局提供相应的发展对策。

凹土-聚己内酯基农药缓释膜的研制

采用浇铸法制备凹土-聚己内酯负载高效氯氰菊酯复合农药缓释膜,并探索了凹土和高效氯氰菊酯对复合膜结构和性能的影响。利用红外光谱(FTIR)仪、X射线衍射(XRD)仪、偏光显微镜(PLM)、扫描电镜(SEM)对所制得的农药缓释膜结构及(亚)微观形貌进行表征,考察了膜的力学性能、润湿性能、透光率及不透明度,研究了农药缓释膜在50%乙醇溶液中的药物释放行为及药物释放机理。结果表明,当凹土含量(质量分数,下同)为10%,高效氯氰菊酯含量为5%时,制得农药缓释膜的断裂伸长率为(20.08±3.92)%,拉伸强度为(3.98±0.69)MPa,接触角为(91.3±0.24)°,不透明度为(20.99±1.69)mm^(-1),具有良好的力学性能和使用性能。农药缓释膜药物释放较为缓慢,其释放机理属于药物扩散和骨架溶蚀相结合。

非硅离型(BOPET)聚酯薄膜的研究进展

BOPET(biaxially orien-ted polyester film)离型聚酯薄膜由于其良好的机械性能,耐高温性、易剥离性,近年来被广泛地应用于皮革转印、电子显示行业过程保护、模切冲型及车衣漆面膜等行业。然而,随着汽车、电子与半导体工业技术的不断进步与发展,一种避免硅污染且兼具环保性能,适用于对表面纯净度和质量等有严格要求的高端制造领域的离型解决方案被广泛提出。因此,寻求一种更加环保、高效的生产技术显得尤为重要,尤其是硅油残留敏感的领域。非硅离型(BOPET)聚酯薄膜通过特殊的表面处理技术和材料配方来实现易剥离的效果,从而表现出其独特的优势。本文概括性地介绍非硅离型(BOPET)聚酯薄膜的发展现状,阐述近年来国内外在此领域的发展成果,包括原料、底涂配方及生产工艺等,并对非硅离型(BOPET)聚酯薄膜技术进行展望。

包装方式对压敏胶带剥离强度保持率的影响

采用一种3M压敏胶带分别贴合3类离型膜,以3M压敏胶带的180°剥离强度为性能评估指标,考察普通包装方式下,不同离型膜对3M压敏胶带剥离强度随放置时间的变化;考察不同包装方式条件下,胶带随放置时间的剥离强度变化;考察23℃,90%RH下,离型膜对3M压敏胶带剥离强度随放置时间的变化。研究发现,在普通包装下,P53-MBR能够使3M胶带剥离强度保持最佳效果;在真空袋+干燥剂的包装条件下,3M压敏胶带贴合离型膜P53-MBR放置不同的时间后,胶带的剥离强度保持率最高;在23°,90%RH下,搭配P53-MBR对3M胶带的剥离强度影响更小。结果表明,3M压敏胶带较为理想的贮存条件是隔绝空气中的水和氧,P53-MBR是3M压敏胶带搭配最佳的离型膜,这对3M压敏胶加工成品出货具有现实意义。

缓释和控释尿素的研究与开发综述

分析了尿素利用率低对环境的影响和尿素在土壤中的释放过程 ,阐述了各种缓释和控释尿素的产品设计、缓释机理和制备方法以及国内外对缓释和控释尿素尤其是包膜尿素的研发进展 ,对提高尿素利用率。

包膜缓释肥的养分释放及其增产效应

包膜缓释肥在20℃水中浸泡72h氮释放量仅为80 1%,而普通复合肥和尿素在浸泡4h就达到了88%以上。包膜缓释肥能显著提高氮磷钾的利用率,使氮素利用率在小麦和玉米上分别比普通复合肥平均提高9 14和5 03个百分点;使磷素利用率分别比普通复合肥平均提高17 52和11 22个百分点;使钾素利用率分别比普通复合肥平均提高8 35和11 26个百分点;小麦、玉米分别增产11 3%和12 6%;能显著提高小麦品质,使粗蛋白含量、湿面筋含量、沉降值和稳定时间各项指标都有明显增加。

我国缓释、控释肥料发展现状、趋势及对策

文章分析了我国化肥生产与应用存在的主要问题，在概述国内外新肥料研究与开发动态的基础上，阐明了我国缓释、控释肥料研究开发的目标和重点。