Synthesis and characterization of hybrid organic-inorganic materials based on EA-MAn-APTES and silica

Poly (EA-MAn-APTES)/silica hybrid materials were successfully prepared fromEthyl acrylate (EA), maleic anhydride (MAn) and tetraethoxysilane (TEOS) in the presence of acoupling agent 3-aminopropyltriethoxysilane (APTES),by free-radical solution polymerization and insitu sol-gel process. The mass fraction of TEOS varied from 0 to 25%. The hybrid materials werecharacterized by the methods of FT-IR spectra, solvent extraction, scanning electron microscope (SEM), transmission electron microscope (TEM), differential scanning calorimetry (DSC) andthermogravimetric analysis (TGA) measuring apparatus to get their structures, gel contents,morphologies, particle sizes and thermal performances. The results show that the covalent bonds arebetween organic and inorganic phases, gel contents in the hybrid materials are much higher, theSiO_2 phase is well dispersed in the polymer matrix, silicon dioxide exist at nanoscale in thecomposites and have excellent thermal stability.

Fabrication of branch-like Aph@LDH-MgO material through organic-inorganic hybrid conjugation for excellent anti-corrosion performance

Layered double hydroxides(LDH)frameworks have shown significant enhancement in stability and reusability,and their tailorable architecture brings new insight into the development of the next generation of hybrid materials,which attracted considerable attention in many fields over the years.One of the factors contributing to the widespread applicability of layered double hydroxides is their adaptable composition,which can accommodate a wide spectrum of potential anionic guests.This exceptional property makes the LDH system simple to adjust for various applications.However,most LDH systems are synthesized in situ in an autoclave at high temperatures and pressures that severely restrict the industrial use of such coating systems.In this study,LDH was directly synthesized on a magnesium alloy that had undergone plasma electrolytic oxidation(PEO)treatment in the presence of ethylenediaminetetraacetic acid,thereby avoiding the use of hydrothermal autoclave conditions.This LDH system was compared with a hybrid architecture consisting of organic-inorganic self-assembly.An organic layer was fabricated on top of the LDH film using 4-Aminophenol(Aph)compound,resulting in a smart hierarchical structure that can provide a robust Aph@LDH film with excellent anti-corrosion performance.At the molecular level,the conjugation characteristics and adsorption mechanism of Aph molecule were studied using two levels of theory as follows.First,Localized orbit locator(LOL)-πisosurface,electrostatic potential(ESP)distribution,and average local ionization energy(ALIE)on the molecular surface were used to highlight localization region,reveal the favorable electrophilic and nucleophilic attacks,and clearly explore the type of interactions that occurred around interesting regions.Second,first-principles based on density functional theory(DFT)was applied to study the hybrid mechanism of Aph on LDH system and elucidate their mutual interactions.The experimental and computational analyses suggest that the highπ-electron density and delocalization characteristics of the functional groups and benzene ring in the Aph molecule played a leading role in the synergistic effects arising from the combination of organic and inorganic coatings.This work provides a promising approach to design advanced hybrid materials with exceptional electrochemical performance.

Evaluation of 4 different bone graft substitutes and autogenous bone grafting in root-end resection osteotomies after retrograde root-filling with Intermediate Restorative Material(IRM):An experimental study in dogs

Purpose: To investigate the periapical tissue response after root end filling with intermediate restorative material (IRM) and filling of the root-end resection bone defects with autogenous bone or a bone graft substitute in comparison to empty controls. Materials and Methods: Vital roots of the second, third and fourth mandibular premolars in six healthy mongrel dogs were apectomized. The root canals were prepared and sealed with IRM following a standardized surgical procedure. The resection bone defects were either filled with autogenous bone (PB) or one of the bone graft substitutes;CERAMENTTM|BONE VOID FILLER, ChronOS?, TigranTM PTG, Easygraft? CLASSIC or left empty. After 120 days the animals were sacrificed and the specimens were analyzed radiologically and histologically. Kruskal-Wallis and Mann-Whitney tests were performed for statistical evaluation. Results: 34 sections were analyzed histologically. The evaluation revealed a variation in the outcome amongst the tested options, regarding reestablishment of the periapical bone healing and inflammatory infiltration in the sections. According to the tested variables, there was no statistical significant difference between the materials when comparing all groups as a whole. When comparing individual materials to each other there was statistical differences among some of the tested materials. Conclusion: The healing outcome after periapical surgery of a five-wall resection defect could not be increased by infill with autogenous bone or bone graft substitutes. The most important factor for the healing outcome in periapical surgery is the quality of the root-end sealing. The healing outcome after some of the tested bone substitutes, might be improved by longer healing time.

Ferroelectric Properties and Applications of Hybrid Organic-Inorganic Perovskites

Hybrid organic-inorganic perovskites （e.g. CH;NH;PbI;） have attracted tremendous attention due to their promise for achieving next-generation cost-effective and high performance optoelectronic devices.These hybrid organic-inorganic perovskites possess excellent optical and electronic properties, including strong light absorption, high carrier abilities, optimized charge diffusion lengths, and reduced charge recombination etc., leading to their widespread applications in advanced solar energy technologies （e.g.high efficiency perovskite solar cells）. However, there is still a lack of investigations regarding fundamental properties such as ferroelectricity in these perovskites.As conventional ferroelectric ceramics are prepared at high temperature and have no mechanically flexibility,low-temperature proceed and flexible perovskite ferroelectrics have become promising candidates and should be exploited for future flexible ferroelectric applications. Here, ferroelectric properties in hybrid organic-inorganic perovskites and several state-of-the-art perovskite ferroelectrics are reviewed. Novel ferroelectric applications of hybrid organic-inorganic perovskites are discussed as well, providing guideline for realizing future high performance and flexible ferroelectric devices.

Effect of Preparation Process of Functional Polymer Active Materials on Properties of Gadolinium Ion Selective Electrode

Recently we have studied the rare earth ion-selective electrodes with active materials of the func-tional polymers and found that the process chosen for the functional polymers had an effect on the propertiesof gadolinium ion selective electrode besides the effects of their structures.1.Effect of preparation process of the grafted polymers on the properties ofgadolinium ion selective electrodesThe electrode membranes which consist of functional polymers as active materials were prepared by re-action of gadolinium chloride with the radiation grafted clmer of acrlic acid and polystyrene of which

Evaluation of Antibacterial Effect by Using a Fibrous Grafted Material Loaded Ag Ligand

To obtain the safety of drinking water, an antibacterial material was prepared by loading silver (Ag) onto fibrous iminodiacetate (IDA) adsorbent, which was synthesized by radiation-induced graft polymerization of glycidyl methacrylate and subsequent chemical modification of the produced epoxy group to an IDA group (IDA-Ag). A total amount of loaded Ag on the IDA-Ag fabric was 0.4 mmol-Ag/g-fabric. From an observation of the IDA-Ag fabric cross section by a scanning electron microscope energy dispersive X-ray spectrometer, Ag was distributed to IDA layer uniformly. As a result of evaluating antibacterial effects by the column mode water flow test with stream water, the effective Ag concentration was monitored 0.05 ppm at irrespective flow rate which was functioned to the antibacterial performance. The antibacterial effects for general bacteria were indicated until BV (BV: steam water volume/IDA-Ag fabric volume) 6000, and for colitis germ legions were completely disinfected until BV 6000.

A Rapid Identification Method for Germplasm Materials Resistant to Citrus Huanglongbing Disease

[Objectives]This study was conducted to develop a rapid identification method for citrus germline materials resistant to Huanglongbing disease and lay a basis for accelerating citrus breeding for resistance to Huanglongbing and increasing the breeding efficiency.[Methods]Thirty-six citrus germplasms suspected to be resistant to citrus Huanglongbing disease were collected.The method of direct high grafting to citrus trees infected with Huanglongbing pathogen was adopted.The resistance of the test materials was identified and evaluated by field symptoms combined with quantitative PCR.It was defined as the top grafting identification method.[Results]The test materials that were grafted in spring started to germinate after one month,and three months late(June 5,2018)typical mottled yellowing on leaves was observed on KH-14 for the first time.After four months(July 5,2018)of top grafting,typical mottled yellowing occurred on 23 materials,and 11 materials showed no such symptom.After six months(September 4,2018)of top grafting,although the growth of KH-18,KH-12,KHY-4,KHY-5 and KHY-6 were normal,yellowing was observed on their leaves.Only KH-21 grew well,and showed no yellow shoots and yellowing leaves.It was identified as the material with resistance to Huanglongbing disease.Quantitative PCR tests on the above six materials showed that KH-21 was negative and other five were positive.Real-time fluorescence quantitative PCR test indicated that the average Huanglongbing bacteria amount in KH-21 was 1870.0 cell/μg DNA,and the average Huanglongbing bacteria amount in the control material was 372285.5 cell/μg DNA,indicating KH-21 was resistant to Huanglongbing bacteria.[Conclusions]The method for infecting bacteria by top grafting takes six months,can detect large amount of seedlings,and is time-saving,efficient,cost-saving and accurate.This method can quickly identify the resistance of citrus varieties to citrus Huanglongbing disease,and can be popularized and used in the identification of citrus Huanglongbing disease resistance.

Comparison of different grafting methods on the effect of‘Candidatus Liberibacter asiaticus'transmission

Grafting is a commonly used method for citrus propagation and transmitting'Candidatus Liberibacter asiaticus'(CLas),the putative causing agent of citrus Huanglongbing(HLB).Optimization of the grafting inoculation methods facilitates the material preparation in HLB research.Citrus buds with CLas were grafted onto healthy sour tangerine(Citrus sunki Hort.ex Tanaka)seedlings by different methods such as top grafting(‘T'grafting and‘V'grafting)and side grafting(abdominal grafting).Along with the symptom observation,titers of CLas in the leaves were detected by RTqPCR monthly.The correlation between the growth status of buds or different grafting methods and the success rate of HLB transmission were analyzed.Our results suggest that sufficient DNA could be extracted to accurately detect the CLas from even only 0.0125 g leaf midrib or branch bark.The probability of CLas transmission was higher in plants inoculated with buds in better growth conditions.The success rate of‘T'grafting was significantly higher than that of side grafting and‘V'grafting.Additionally,in terms of HLB transmission efficiency,the two-bud grafting scheme was superior to the single-bud and three-bud grafting schemes.In conclusion,the grafting combinations with the highest HLB transmission efficiency were screened to provide a methodological reference for the practice or research of grafting to obtain plant material.

Modern Composite Materials and Technical Strategies in Posttraumatic Augmentation Rhinoplasty

The selection of ideal posttraumatic augmentation rhinoplasty materials and technical strategies has always been a pressing challenge.Owing to the complexity of the traumatic nasal anatomical structure,such procedures are more complicated than ordinary cosmetic rhinoplasty.The choice of reconstruction material should emphasize its inherent characteristics,such as biocompatibility,anti-infective ability,strength,and plasticity.With the development of rhinoplasty,the choice of material is less limited and composite materials have become mainstream.This review outlines current composite materials and techniques in posttraumatic augmentation rhinoplasty.

蔬菜嫁接砧穗互作分子机制研究进展

嫁接技术是园艺作物增产、改良品质和增强抗逆性最经济有效的手段之一,其应用范围仍在不断扩大。除了要求嫁接技术不断提高外,还需进一步探索嫁接亲和性与砧穗互作的机制。嫁接成活包括一系列的生理、生化过程,嫁接激活、激素通路或参与维管束形成相关基因都有可能参与嫁接组织的再生重建,明确其调控机制具有重要意义。嫁接是砧木/接穗相互识别与作用的过程,砧穗间长距离信号传导是理解嫁接生理的基础。不同基因型的砧木/接穗嫁接组合,嫁接植株在生长发育、表型、产量及胁迫抗性方面表现不同。本文就蔬菜嫁接砧穗互作分子机制的研究进展进行综述,如嫁接成活、砧穗间遗传信号传递、嫁接与表观遗传变化及嫁接与基因表达,以期为深入研究蔬菜嫁接分子机制提供理论参考,为砧木选择和蔬菜种质材料创新提供指导。

自体软组织替代材料治疗天然牙牙龈退缩的Meta分析

目的:从临床指标方面系统评价并比较自体软组织替代材料与结缔组织移植物联合冠向复位瓣技术治疗天然牙牙龈退缩的疗效。方法:计算机检索PubMed、EMBASE、Web of Science、维普、万方、知网等数据库中关于自体软组织替代材料或结缔组织移植物(CTG)治疗牙龈退缩的随机对照试验,检索时限从2013年1月至2023年12月。结果:最终纳入14个随机对照研究,1117个牙龈退缩位点。Meta分析显示,术后6个月时,CTG与异种胶原基质(XCM)比较能更好地降低牙龈退缩深度,与富血小板纤维蛋白(PRF)、脱细胞真皮基质(ADM)比较无明显区别;CTG与PRF、ADM、XCM比较角化龈宽度增量更明显;根面覆盖率指标差异无统计学意义;PRF、XCM可以明显降低患者术后的疼痛感。结论:研究表明,自体软组织替代材料与CTG相比,对于治疗牙龈退缩的效果并没有显著差异,但是前者可以降低患者术后疼痛感。

棉短绒纤维素/聚丙烯酰胺复合水凝胶的合成及絮凝性能研究

以棉短绒(MCC)为原料､丙烯酰胺(Acrylamide,AM)为单体､过硫酸铵(Ammonium persulfate,APS)为引发剂､N,N′-亚甲基双丙烯酰胺(N,N′-Methylenebisacrylamide)为交联剂,采用水溶液聚合的方式共聚制备水凝胶绿色絮凝材料。考察了体系共聚时间､共聚温度､APS投加量和单体质量比对接枝率的影响。利用红外光谱(FT-IR)､X射线衍射(XRD)､热重分析(TG)､扫描电镜(SEM)和Zeta电位等对所制备的材料进行表征,并考察其对高岭土模拟废水的絮凝效果。结果表明,当AM与MCC质量比为5∶1､引发剂投加质量为0.06 g､反应温度为50℃､反应时间为3 h时,可制得较高接枝率的产品,且其对pH为3､7､11高岭土悬浊液(300 mg/L)的浊度去除率分别达到98.6%､97.6%和98.3%,表现出良好的絮凝性能。

脱矿牙本质基质和脱细胞牙本质基质成骨效果的对比研究

目的比较骨缺损区植入脱矿牙本质基质和脱细胞牙本质基质的成骨效果。方法制备脱矿牙本质基质和脱细胞牙本质基质。将24只SPF级SD雄性大鼠随机分为脱矿组(A组)、脱细胞组(B组)、Bio-Oss骨粉组(C组)、空白组(D组),每组6只大鼠,在麻醉条件下制备双侧股骨骨缺损。A、B、C组大鼠分别在骨缺损区植入脱矿牙本质基质、脱细胞牙本质基质、Bio-Oss骨粉,D组大鼠不植入任何材料。术后4周和8周,每组各随机处死3只大鼠。大体观察骨缺损区愈合情况,血清学检测成骨指标骨形态发生蛋白(BMP)-2及碱性磷酸酶(ALP)浓度,影像学观察骨缺损区高密度灰色区(代表骨愈合)分布情况,组织形态学观察新骨形成情况,计算新骨形成率。结果术后4周和8周,大体观察见A组成骨能力较其他组活跃,血清学检测A组BMP-2及ALP浓度均高于其他组,差异有统计学意义(P<0.05)。8周时,影像学观察可见A组骨缺损区高密度灰色区分布均匀,组织形态学观察见A组排列规则的骨基质。A组4、8周时的新骨形成率分别为28.51%±0.55%、32.57%±2.28%,均高于其他组,差异有统计学意义(P<0.05)。结论脱矿牙本质基质比脱细胞牙本质基质具有更好的成骨潜能。

煤气化细渣基吸附剂的CO_(2)吸附性能

吸附法是碳捕集的主要途径之一。氨基功能化多孔材料作为重要的CO_(2)吸附剂,通常以价格高昂的介孔分子筛为载体,这极大地限制了吸附法的规模化应用。因此,降低载体成本对于碳捕集有着重要的现实意义。使用盐酸处理煤气化细渣(FS)制得酸浸渣材料(AFS),进一步嫁接3-氨丙基三乙氧基硅烷(APTES)制备氨基功能化CO_(2)吸附材料(AFS-A-x)。利用热重分析(TG-DTG)、傅立叶变换红外光谱分析(FTIR)和低温N2吸脱附等方法对样品进行表征,利用高压气体吸脱附仪(PCTPro)考察FS,AFS和AFS-A-x的CO_(2)吸附性能,建立等温吸附模型,并计算等量吸附热。结果表明:相较于FS,AFS的硅羟基含量更高,孔隙结构更丰富,更适合做嫁接原材料。在60℃,0.1 MPa的吸附条件下,AFS-A-3材料的CO_(2)吸附量较AFS材料的CO_(2)吸附量提高了19.6%,达到0.61 mmol/g,在30℃~70℃的温度范围内,AFS-A-3的吸附性能随温度上升而下降;相同条件下,在低压段(0 MPa~0.015 MPa)AFS-A-3的吸附能力明显高于AFS的吸附能力,说明AFS-A-3在低CO_(2)分压条件下有更高的应用潜力;经过十次吸脱附循环后,AFS-A-3在60℃,0.1 MPa条件下对CO_(2)的吸附量下降了5%;AFS和AFS-A-3的等温吸附曲线可用Langmuir模型较好描述。相比于AFS,嫁接改性的AFS-A-3对CO_(2)的等量吸附热明显增加,据此推断吸附类型由物理吸附主导转变为物理吸附与化学吸附共同作用。

可降解锌基合金在骨缺损修复重建中的应用及研究热点和不足

背景:锌基合金医用植入材料有优异的力学性能、完全可降解性、良好的生物相容性,主要用于骨科植入物、心血管支架、胆管支架、气管支架、神经导管等。目的:综述可降解锌基合金应用于骨缺损修复的研究进展,展望锌基材料可期研究方向与成果。方法:检索PubMed、Web of Science、万方及中国知网数据库,选择各数据库建库至2023年6月收录的各类可降解锌基合金用于骨植入材料研究的相关文献,对生物可降解锌基合金的基本特性进行概述,对锌基合金促进骨组织修复作用进行梳理和归纳总结,讨论当前的研究热点与不足。结果与结论:①锌基合金具备良好的生物相容性,以锌基合金为基体材料,借助支架结构构建技术和涂层优化工艺将有效提高锌基合金的骨传导性,并且使其降解产物具备高效骨诱导性,以调控成骨、破骨细胞的基因表达,促进骨缺损后的修复重建;②然而在锌基合金优化的研究中,涂层工艺相对不足,增材负载技术尚缺乏;③锌基合金拥有良好的机械、生物特性,通过特殊工艺可增加材料的骨传导性、骨诱导性以有效提高其促进骨修复重建能力,并有望进一步实现个性化移植材料的研发。优化涂层与增材负载等技术融合于锌基合金的研究有待进一步探讨。

化学接枝聚乙二醇单甲醚的氧化石墨烯/聚丙烯相变材料

在聚乙二醇单甲醚(MPEG)中引入具有三嗪环结构的2-氨基-4,6-二氯-1,3,5-三嗪(ADCT),将MPEG的-OH接枝在ADCT的三嗪环4、6位制备具有三嗪环结构的MPEG(ADMT),然后负载于载体材料氧化石墨烯(GO)得到定形相变材料(FSPCM),利用双螺杆挤出机将FSPCM与聚丙烯(PP)熔融共混,制备FSPCM质量比为5%、10%、15%的PP/FSPCM共混材料,并采用^(1)HNMR、FT-IR、DSC、热台测试等试验手段对ADMT、FSPCM、PP/FSPCM共混材料进行表征。研究结果表明:FSPCM结晶焓值为96.1J·g^(-1),在250℃下仍保留较好的定形效果。10%质量比的PP/FSPCM相变焓值为9.10J·g^(-1),焓值效率为60.7%。

生物材料在上颌窦内提升术中的临床应用进展

上颌后牙区常因缺牙后牙槽骨吸收或上颌窦气化导致剩余骨量不足,造成种植修复困难,上颌窦内提升术作为其解决方案之一也在一定程度上受到骨量限制。随着材料学的发展,包括自体骨、同种异体骨、异种骨、合成骨移植材料等骨增量材料以及血小板浓缩物等骨移植辅助材料在医学领域逐渐广泛应用,上颌窦内提升术的适应证得到进一步扩大。将两种或几种材料复合使用或研发复合型材料以实现多种材料性能的互补可能是未来的发展趋势,既能兼顾各种材料的特点,达到更好的成骨效果,还能缩短成骨时间。

离子交联型石蜡基导热增强定型相变材料的制备及其性能

对石蜡(PA)进行接枝改性、自乳化得到PA乳液。在乳液颗粒形态下将接枝产物分散在乳化层,常温条件下通过乳液颗粒间的空间分布及离子交联,对导热材料形成内锁、铆结,并加Cu粉增强导热制备了PA基导热增强定型相变材料(记作PA@Cu),与定量PA于80℃浸渍吸附20 min,得到吸附PA的PA@Cu(记作PA@Cu-PA),并研究了其元素结构、表观形貌、相变焓、导热性能、热稳定性。结果表明:当Cu粉用量为16 g时,PA@Cu-PA导热系数0.468 W/(m·K),结晶焓-133.27 J/g,在85℃时无明显泄漏,热分解温度384.5℃,储能性能与热稳定性能良好。

用于高分子材料改性领域的无机纳米填料化学改性方法

综述了对高分子材料中广泛使用的无机纳米填料进行表面化学改性的方法,包括偶联剂改性法、酯化改性法等小分子改性剂法,以及表面原位接枝聚合改性等大分子接枝法。这些方法不仅解决了无机纳米填料易团聚、分散性差及与高分子材料复合相容性不佳的问题,而且有效地提升了其在电子、催化、能源、生物医学等领域的应用性能。同时介绍了各种方法的改性机理、适用条件和优缺点,并对改性方法的工艺优化和发展研究方向进行了展望。

Lyocell纤维非织造材料的吸湿改性研究

为提高Lyocell纤维的吸湿性,以三聚氯氰为载体,通过化学改性在Lyocell纤维表面接枝引入氨基酸等极性基团。分析了不同碱处理浓度、浸碱时间、反应温度、反应时间下各组试样的吸湿性,并对改性前后的形貌、结构、力学性能进行对比。结果表明:质量分数5%的NaOH溶液处理30 min,添加制备的多羧基氨基三聚氯氰衍生物中间体,在90℃条件下反应6 h,Lyocell纤维水刺材料的吸湿效果最好,且仍具备良好的力学性能,可满足高吸湿性水刺非织造材料的使用要求。