Calcium Sulfate

硫酸钙
  • 文章类型: Journal Article
    使用可植入抗生素珠已经成为管理人类和兽医学中手术部位感染的常用治疗方式。这项研究的目的是描述来自市售硫酸钙抗生素递送试剂盒的五种抗生素的洗脱动力学。次要目标是比较来自佛罗里达大学兽医微生物学实验室数据库的常见细菌的洗脱浓度与最小抑制浓度(MIC)。
    将硫酸钙粉末与阿米卡星合用,头孢唑啉,庆大霉素,氨苄西林/舒巴坦,还有美罗培南.将三个负载抗生素的珠子一式三份浸入5mL磷酸盐缓冲盐水(PBS)中,并在恒定搅拌下保持在37°C。在1小时至30天的14个时间点对抗生素调节的PBS取样,并通过液相色谱法分析以确定抗生素浓度。
    在30天采样期间,所有珠子洗脱的抗生素浓度,除了氨苄西林/舒巴坦,在第一周内洗脱的抗生素最多。前3-9天内洗脱液中抗生素的浓度(3毫米和5毫米珠,分别)大于常见分离株的MIC。5mm珠样品在较长时间内保持较高的浓度方面表现优异,与3毫米珠子相比。
    CSH珠在30天的研究过程中洗脱抗生素。大多数抗生素洗脱发生在第一周内,并保持在通常遇到的分离株的MIC以上。该信息对于治疗实践中遇到的局部感染的临床决策可能是有用的。
    UNASSIGNED: The use of implantable antibiotic beads has become a frequent treatment modality for the management of surgical site infections in human and veterinary medicine. The objective of this study is to describe the elution kinetics of five antibiotics from a commercially available calcium sulfate antibiotic delivery kit. A secondary goal was to compare elution concentrations with minimal inhibitory concentrations (MIC) for commonly encountered bacteria from the University of Florida\'s veterinary microbiology laboratory database.
    UNASSIGNED: Calcium sulfate powder was combined with amikacin, cefazolin, gentamicin, ampicillin/sulbactam, and meropenem. Triplicates of three antibiotic-loaded beads were immersed in 5 mL of phosphate-buffered saline (PBS) and kept at 37°C under constant agitation. Antibiotic-conditioned PBS was sampled at 14 time points from 1-h to 30 days and analyzed by liquid chromatography to determine the antibiotic concentration.
    UNASSIGNED: All beads eluted concentrations of antibiotics for the 30-day sampling period, except for ampicillin/sulbactam, with the most antibiotics being eluted within the first week. The concentration of antibiotics within the eluent within the first 3-9 days (3- and 5-mm beads, respectively) was greater than the MIC of common isolates. The 5 mm bead samples were superior in maintaining higher concentrations for a longer period, compared to the 3-mm beads.
    UNASSIGNED: CSH beads eluted antibiotics over the 30-day course of the study. Most of the antibiotic elution occurred within the first week and was maintained above the MIC of commonly encountered isolates. This information may be useful for clinical decision making for treatment of local infections encountered in practice.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    磷石膏(PG)胶结膏体回填(CPB)是处理PG的主要非危险方法。然而,使用水泥等传统粘合剂会增加全球碳排放量和采矿运营成本,同时降低氟化物浸出风险。本研究介绍了一种新型的基于PG的CPB处理方法,该方法使用钢渣(SS)和磨碎的粒状高炉渣(GGBFS)作为粘合剂,氧化钙作为激发剂,用生物炭作为氟化物固定剂。我们研究了添加生物炭对SS和GGBFS-PG基材料(SSPC)中氟化物的水合和固化/稳定(S/S)的影响。结果表明,添加0.2wt%的生物炭可实现氟化物S/S的最佳强度和性能。与不含生物炭的对照组相比,强度增加了54.3%,SSPC固化28天后,F浸出下降了39.4%。添加0.2wt%的生物炭促进了异质成核并充当微填料,增强SSPC的属性。然而,过量的生物炭降低了SSPC的致密性。此外,氟化物的分布与P密切相关,Ca,Fe,Al,这表明氟化物S/S与氟磷灰石等稳定水合产物的形成有关,萤石,和复合物如[AlF6]3-和[FeF6]3-。这些发现为PG的安全处理以及SS和GGBFS的固体废物的有益再利用提供了有希望的方法。
    Phosphogypsum (PG) cemented paste backfill (CPB) is a primary non-hazardous method for treating PG. However, using traditional binders like cement increases global carbon emissions and mining operational costs while complicating the reduction of fluoride leaching risks. This study introduces a novel PG-based CPB treatment method using steel slag (SS) and ground granulated blast furnace slag (GGBFS) as binders, calcium oxide as an exciter, with biochar serving as a fluoride-fixing agent. We investigated the effect of biochar addition on the hydration and solidification/stabilization (S/S) of fluoride in SS and GGBFS-PG-based materials (SSPC). The results indicated that the optimal strength and performance for fluoride S/S were achieved with a biochar addition of 0.2 wt%. Compared to the control group without biochar, the strength increased by 54.3%, and F leaching decreased by 39.4% after 28 days of curing for SSPC. The addition of 0.2 wt% biochar facilitated heterogeneous nucleation and acted as a microfiller, enhancing SSPC\'s properties. However, excessive biochar reduced the compactness of SSPC. Additionally, the distribution of fluoride was strongly correlated with P, Ca, Fe, and Al, suggesting that fluoride S/S is linked to the formation of stable hydration products like fluorapatite, fluorite, and complexes such as [AlF6]3- and [FeF6]3-. These findings offer a promising approach for the safe treatment of PG and the beneficial reuse of solid waste from SS and GGBFS.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    玉米象鼻虫,西马西斯·莫舒尔斯基,1855年(鞘翅目:孔雀科),通常在储存的谷物中达到害虫状态。化学控制是最常用的种群抑制方法,这可能会造成不利影响,因此,需要使用惰性粉末等替代品。本工作旨在在实验室中验证不同浓度的不同类型的惰性粉末对S.zeamamais死亡率的影响。为此,实验以完全随机的设计进行,有13次治疗和4次重复,每次复制十个成年人,其中不同惰性粉末(玄武岩粉末,石膏粉,和硅藻土)在0.025g的浓度下进行测试,0.05g,0.1克和0.2克/20克玉米粒。Variance,常态,除控制效率(CE%)外,还应用了同方差检验,中位致死时间(TL50),和生存曲线。所有的治疗都导致了S.zeamamais的死亡,硅藻土的所有浓度都更有效,20天死亡率100%,然后处理0.2克石膏粉/20克玉米粒,具有卓越的效率,在20天内达到95%,在30天内达到100%。结果表明,硅藻土处理的死亡率最高,平均存活时间最好。
    The maize weevil, Sitophilus zeamais Motschulsky, 1855 (Coleoptera: Curculionidae), generally reaches pest status in stored grain. Chemical control is the most used method for population suppression, which can cause adverse impacts, thus creating a need for alternatives such as using inert powders. The present work aims to verify the effect of different concentrations of different types of inert powders on the mortality of S. zeamais in the laboratory. To this end, the experiments were carried out in a completely randomized design, with 13 treatments and four replications, ten adults per replication, where the effect of different inert powders (basalt powder, gypsum powder, and diatomaceous earth) was tested at concentrations of 0.025 g, 0.05 g, 0.1 g and 0.2 g/20 g of corn grains. Variance, normality, and homoscedasticity tests were applied in addition to controlling efficiency (CE%), median lethal time (TL50), and survival curves. All treatments caused mortality in S. zeamais, and all concentrations with diatomaceous earth were more efficient, with 100% mortality at 20 days, followed by the treatment of 0.2 g of gypsum powder/20 g of corn grains, with superior efficiency, to 95% in 20 days and 100% in 30 days. The results indicated that treatments with diatomaceous earth had the highest mortality rate and the best average survival time.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    在大自然中,手性氨基酸与晶体之间的选择性相互作用对于手性生物矿物的形成很重要,并且可以深入了解同手性的神秘起源。这里,我们表明,具有不同亲水性/疏水性的手性氨基酸在动态生长的石膏[001]步骤中表现出不同的手性选择性偏好。亲水性氨基酸对其d-异构体表现出手性选择性,而疏水性氨基酸更喜欢它们的l-异构体。手性识别的这些差异可以归因于生长石膏的[001]步骤中亲水性和疏水性氨基酸之间的立体化学匹配不同。由氨基酸亲水性/疏水性导致的这些不同的手性选择性通过从动态步骤上的纳米调节的实验结晶研究得到证实。对石膏形态的微观改性,和宏观降水。此外,随着氨基酸亲水性的增加,手性选择的差异增加;相反,氨基酸疏水性的增加导致手性选择的下降。这些见解提高了我们对氨基酸和晶体之间相互作用机制的理解,并提供了对手性生物矿物的形成过程和自然界中同手性起源的见解。
    In nature, selective interactions between chiral amino acids and crystals are important for the formation of chiral biominerals and provide insight into the mysterious origin of homochirality. Here, we show that chiral amino acids with different hydrophilicities/hydrophobicities exhibit different chiral selectivity preferences in the dynamically growing gypsum [001] steps. Hydrophilic amino acids show a chiral selectivity preference for their d-isomers, whereas hydrophobic amino acids prefer their l-isomers. These differences in chiral recognition can be attributed to the different stereochemical matching between the hydrophilic and hydrophobic amino acids on the [001] steps of growing gypsum. These different chiral selectivities resulting from the amino acid hydrophilicity/hydrophobicity are confirmed by the experimental crystallization investigations from nano regulation on dynamic steps, to microscopic modification of gypsum morphology, and to macroscopic precipitation. Furthermore, as the hydrophilicity of amino acids increases, the disparity in chiral selection rises; conversely, the increase in the hydrophobicity of amino acids results in a decline in chiral selection. These insights improve our understanding of the interaction mechanism between amino acids and crystals and provide insights into the formation process of chiral biominerals and the origin of homochirality in nature.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    磷石膏,磷化学工业中的典型副产品,在降雨和长期堆积过程中会产生大量含磷酸盐和氟化物的渗滤液,这不仅造成严重的环境污染,还会导致资源的浪费。在这项研究中,提出了氢氧化钙沉淀和镧沸石(La-ZFA)吸附的联合处理,以实现从磷石膏渗滤液中回收磷酸盐和氟化物。在磷石膏中,除磷以外,大多数磷都可以以残留赋存形式浸出,而对于氟化物,只有水溶性F才能有效浸出。磷酸盐和氟化物的最佳浸出量分别为22.59和4.64mg/g,分别,液固比400:1,浸出时间120分钟,pH值6.0,粒度>200目(<0.075mm),浸出温度为25℃。以Ca(OH)2为沉淀剂,通过控制pH和时间,可以从磷石膏渗滤液中选择性沉淀磷酸盐,在pH10.0时,其浓度显着降低至0.29mg/L,去除率为99.48%。XRD,SEM和VisualMINTEQ软件分析证明沉淀物的主要成分是羟基磷灰石(Ca5(PO4)3(OH))。P沉淀后,研究了一系列氟化物吸附剂,选择了La-ZFA吸附剂,并将其用于通过循环固定床柱从渗滤液中回收氟化物。La-ZFA的效率基本上不受高浓度硫酸盐的影响,它可以选择性地从磷石膏渗滤液中吸附氟化物,导致废水中的最终氟化物浓度为0.29mg/L。表征表明,氟化物可能通过与羟基的配体交换吸附到La-ZFA上。本研究中提出的方法有望从磷石膏的渗滤液中依次回收磷酸盐和氟,对磷石膏的资源化利用和管理具有重要的指导意义。
    Phosphogypsum, a typical by-product in the phosphorus chemical industry, could generate a large amount of leachate containing phosphate and fluoride in the process of rainfall and long-term stacking, which not only causes serious environmental pollution, but also leads to a waste of resources. In this study, a united treatment of calcium hydroxide precipitation and lanthanum zeolite (La-ZFA) adsorption was proposed to achieve the recovery of phosphate and fluoride from phosphogypsum leachate. In phosphogypsum, most phosphorus could be leached except P in the residual occurrence form, while for fluoride, only water-soluble F could be effectively leached. The optimum leaching amounts of phosphate and fluoride were 22.59 and 4.64 mg/g, respectively, at liquid-solid ratio of 400:1, leaching time of 120 min, pH of 6.0, particle size of >200 mesh (<0.075 mm), and leaching temperature of 25°C. Using Ca(OH)2 as the precipitant, the phosphate could be precipitated selectively from phosphogypsum leachate by controlling pH and time, and the concentrations of it decreased significantly to 0.29 mg/L at pH 10.0, with a removal efficiency of 99.48%. XRD, SEM and Visual MINTEQ software analysis proved that the main component of the precipitate was hydroxyapatite (Ca5(PO4)3(OH)). After P precipitation, a series of sorbents for fluoride were investigated, and La-ZFA sorbent was chosen and utilized to recover the fluoride from the leachate through a cyclic fixed-bed column. The efficiency of La-ZFA was basically not affected by the high concentration sulfate, and it can selectively adsorb fluoride from phosphogypsum leachate, leading to a final fluoride concentration of 0.29 mg/L in the effluent. The characterization demonstrated that fluoride might be adsorbed onto the La-ZFA via ligand exchange with hydroxy groups. The proposed method in this study is expected to sequentially recover phosphate and fluorine from the leachate of phosphogypsum, and it has great guiding significance for resource utilization and management of phosphogypsum.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    今天,内石器时代微生物定植的生物多样性仅被部分理解。在这项研究中,我们使用16SrRNA基因的分子群落元转录的组合,光学显微镜,CT扫描分析,和拉曼光谱来描述波兰南部和以色列北部2个地点的石膏内石器群落。所获得的结果表明,尽管地理区域不同,气候条件,以及定居石膏露头的物理特征,这两个位点具有非常相似的微生物和色素组成。蓝细菌主导着两个石膏栖息地,其次是Chloroflexi和Pseudomonadota。在蓝细菌中,以色列的嗜热球菌科更为丰富,而波兰的嗜热球菌科则更为丰富。有趣的是,在波兰没有发现弧菌科的序列,只有在以色列。一些获得的蓝藻16SrRNA基因序列与以前检测到的来自不同底物和地理区域内石器群落的序列相匹配,支持全球元社区的假设,但是仍然需要更多的数据。利用拉曼光谱,与类胡萝卜素一起检测到了蓝藻紫外线筛选色素-镰刀素和gloeocapsin,叶绿素a和黑色素.这些色素可以作为蓝细菌基本分类学鉴定的潜在生物标志物。总的来说,这项研究提供了更多的见解,在不同地区的石膏中蓝细菌内体定植的多样性。
    Today, the biodiversity of endolithic microbial colonisations are only partly understood. In this study, we used a combination of molecular community metabarcoding using the 16S rRNA gene, light microscopy, CT-scan analysis, and Raman spectroscopy to describe gypsum endolithic communities in 2 sites-southern Poland and northern Israel. The obtained results have shown that despite different geographical areas, climatic conditions, and also physical features of colonized gypsum outcrops, both of these sites have remarkably similar microbial and pigment compositions. Cyanobacteria dominate both of the gypsum habitats, followed by Chloroflexi and Pseudomonadota. Among cyanobacteria, Thermosynechococcaceae were more abundant in Israel while Chroococcidiopsidaceae in Poland. Interestingly, no Gloeobacteraceae sequences have been found in Poland, only in Israel. Some of the obtained 16S rRNA gene sequences of cyanobacteria matched previously detected sequences from endolithic communities in various substrates and geographical regions, supporting the hypothesis of global metacommunity, but more data are still needed. Using Raman spectroscopy, cyanobacterial UV-screening pigments-scytonemin and gloeocapsin have been detected alongside carotenoids, chlorophyll a and melanin. These pigments can serve as potential biomarkers for basic taxonomic identification of cyanobacteria. Overall, this study provides more insight into the diversity of cyanobacterial endolithic colonisations in gypsum across different areas.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    背景:考虑到髋关节置换术后感染率的增加,目前的选择之一是在感染部位应用生物复合材料。使用的产品之一是Stimulan,一种完全可吸收的硫酸钙,用于治疗急性和慢性感染。这种生物复合材料具有受控的纯度,很容易与液体混合,粉末,和抗生素,可以直接应用于感染部位,也可以注射.方法:我们分析了76例患者的数据,他们于2017年1月至2023年9月期间入住Galati县急诊临床医院“St.ApostolAndrei”,诊断为与髋关节置换术相关的感染。结果:69.73%的病例(52例),我们决定把植入物留在原处.在这个子群中,应用刺激素26例(57.78%)。其中,100%治愈-与未应用Stimulan的亚组相比,这个百分比较低。所有患者都接受了化学和机械厕所,24名患者(20.27%),有必要在使用或不使用Stimulan的情况下消融植入物,然后再植入假体.结论:Stimulan患者平均住院时间较长,其中近一半需要在两个时期进行干预,四分之一需要植入间隔物。然而,治愈率较高,只有三个人无法控制感染,也没有死亡.这项研究证实了在急性和慢性病例的经典治疗之外使用生物复合材料时治疗的有效性。
    Background: Given the increasing rate of infections following hip arthroplasty, one of the current options is the application of a biocomposite at the site of the infection. One of the products used is Stimulan, a completely resorbable calcium sulfate, designed to treat acute and chronic infections. This biocomposite has a controlled purity, is easy to mix with liquid, powder, and antibiotics, and can be applied directly to the site of infection, or it can be injected. Methods: We analyzed data from 76 patients, who were admitted to the County Clinical Hospital of Emergency \"St. Apostol Andrei\" in Galati during January 2017-September 2023, with a diagnosis of infection associated with hip arthroplasty. Results: In 69.73% of cases (52 patients), we decided to keep the implant in place. In this subgroup, Stimulan was applied in 26 cases (57.78%). Of these, 100% were cured-compared to the subgroup in which Stimulan was not applied, where this percentage was lower. All patients underwent chemical and mechanical toileting, and for 24 patients (20.27%), it was necessary to ablate the implant with or without the application of Stimulan, then reimplantation of the prosthesis. Conclusions: The patients with Stimulan had a longer average length of hospitalization, almost half of them required intervention in two periods, and a quarter required the implantation of spacers. However, the cure rate was higher, only in three people could we not control the infection, and there was no death. This study confirms the effectiveness of the treatment when using a biocomposite in addition to the classical treatment for both acute and chronic cases.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Clinical Trial Protocol
    背景:拔牙手术通常会导致骨吸收,这可能会对牙槽骨的尺寸产生不利影响。研究表明,在这种情况下,使用骨移植替代品的插座保存技术可以有效地减少早期骨丢失。α-硫酸钙半水合物(α-CSH)作为一种潜在的骨移植材料,由于其良好的性能而受到了广泛的关注。包括骨传导性,血管生成潜力,和生物相容性。考虑到这些事实,我们开发了应用α-CSH解决拔牙后牙槽骨丢失的初步方案。
    目的:这项研究的总体目标是评估α-CSH作为拔牙后保留牙槽的骨诱导移植材料的可行性和初始有效性。
    方法:这项初步临床试验将涉及30个来自18-35岁个体的新鲜拔牙槽。参与者将分为2组:一组将在拔牙后接受α-CSH移植材料以保存牙槽,而另一组不会接受任何移植材料。在整个研究过程中,将密切监测参与者的安全措施,其中包括临床检查,射线成像,和血液测试。射线照相成像将被广泛地用于辅助骨形成的进展。
    结果:该研究于2022年8月开始注册,并计划于2023年底结束后评估和分析。这项研究的结果预计将在2024年底公布。
    结论:这项临床研究代表了在人类中评估α-CSH在牙槽骨再生中的可行性和功效的初步研究。我们假设包含α-CSH可以大大加快新鲜插座内骨形成的过程,导致骨高度的迅速恢复,而没有与收获自体骨移植物相关的缺点。
    背景:印度尼西亚注册中心INA-D02FAHP;https://tinyurl.com/2jnf6n3s。
    DERR1-10.2196/49922。
    BACKGROUND: Tooth extraction procedures often lead to bone resorption, which can have adverse effects on the dimensions of the alveolar ridge. Research has shown that socket preservation techniques using bone graft substitutes can effectively minimize early bone loss in such cases. α-calcium sulfate hemihydrate (α-CSH) has garnered significant attention as a potential bone graft material due to its favorable properties, including osteoconductivity, angiogenic potential, and biocompatibility. Considering these facts, we developed a preliminary protocol for applying α-CSH in addressing alveolar bone loss following tooth extraction.
    OBJECTIVE: This research\'s general objective is to evaluate the feasibility and initial effectiveness of α-CSH as bone-inducing graft material for socket preservation after tooth extraction.
    METHODS: This preliminary clinical trial will involve 30 fresh extraction sockets from individuals aged 18-35 years. The participants will be divided into 2 groups: one group will receive α-CSH graft material after tooth extraction for socket preservation, while the other group will not receive any graft material. Throughout the study, the participants will be closely monitored for safety measures, which will include clinical examinations, radiographic imaging, and blood tests. Radiographic imaging will be used extensively to assist the progress of bone formation.
    RESULTS: The study commenced enrollment in August 2022 and is scheduled to conclude post assessments and analyses by the end of 2023. The results of the study are anticipated to be accessible in late 2024.
    CONCLUSIONS: This clinical study represents the initial investigation in humans to assess the feasibility and efficacy of α-CSH in alveolar bone regeneration. We hypothesize that the inclusion of α-CSH can greatly expedite the process of bone formation within fresh sockets, resulting in a swift restoration of bone height without the disadvantages associated with harvesting autogenous bone graft.
    BACKGROUND: Indonesia Registry Center INA-D02FAHP; https://tinyurl.com/2jnf6n3s.
    UNASSIGNED: DERR1-10.2196/49922.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    Humans processed gypsum for their everyday use at least 7000 years ago. They have been using fixed limb methods for fracture treatment for nearly 5000 years. Hippocrates recognized the importance of the splint and the \"roller bandage\" for fracture treatment, and made the bandage hard by adding wax, pitch, lard or resin to the multi-layer cloth bandage, but not gypsum. Arabian physician El Zahrawi (936 -1013) also described a clay glue mixture, and flour and egg white as fracture fixation materials. From 970, Persian physician Muwafak used gypsum as the exclusive material for fracture fixation. The rudimentary form of modern plaster bandages was developed in the mid-19th century and spread widely after that, using methods from the Russian Pyrogov by soaking canvas in a gypsum slurry and Dutchman Massson wrapped gypsum powder in cotton cloth strips.
    人类加工和使用石膏并用于建筑和生活用具中至少有7 000年的历史。而将石膏用于骨折固定,首次文献记载是在公元970年,波斯医师穆瓦法克用石膏浆浇注的方法固定小腿骨折。虽然从希波克拉底时代开始,在欧洲大陆、埃及、中国等地区,先后有在绷带上添加蜡、沥青、油脂或树脂,以及粘土胶混合物、面粉和蛋清等物质使绷带变硬的方法,但均不能像石膏那样快速硬化。直到19世纪中期,分别由俄国的皮罗戈夫用帆布浸泡在石膏浆中的方法,以及荷兰的马西森用布条包夹石膏粉的方法,才形成了现代石膏绷带的雏形,并迅速在全世界推广。.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    在这项工作中,探索了合成硫酸钙(CaSO4·nH2O)材料用于遗产保护的生物启发策略的潜力。为此,提出了一种非经典的多步骤结晶机理,以了解钙黄绿素-一种对二价阳离子具有高亲和力的荧光螯合剂-对硫酸钙相的成核和生长的影响。从纳米尺度到宏观尺度,该策略为设计和生产荧光纳米bassanite(NB-C;CaSO4·0.5H2O)奠定了基础,应用作为一种完全兼容的固结剂,用于保护历史石膏板。一旦应用于石膏(CaSO4·2H2O)石膏标本,胶结在水合纳米-massanite导致机械强度的显着增加,而钙黄绿素在新形成的石膏水泥中的晶体内闭塞改善了其耐候性。此外,在紫外线照射下,由钙黄绿素分子产生的发光被封闭在石膏晶体中形成的纳米babranite水合允许在处理的石膏灰泥中容易地识别新沉积的固结剂而不改变基底的外观。
    In this work, the potential of bio-inspired strategies for the synthesis of calcium sulfate (CaSO4·nH2O) materials for heritage conservation is explored. For this, a nonclassical multi-step crystallization mechanism to understand the effect of calcein- a fluorescent chelating agent with a high affinity for divalent cations- on the nucleation and growth of calcium sulfate phases is proposed. Moving from the nano- to the macro-scale, this strategy sets the basis for the design and production of fluorescent nano-bassanite (NB-C; CaSO4·0.5H2O), with application as a fully compatible consolidant for the conservation of historic plasterwork. Once applied to gypsum (CaSO4·2H2O) plaster specimens, cementation upon hydration of nano-bassanite results in a significant increase in mechanical strength, while intracrystalline occlusion of calcein in newly-formed gypsum cement improves its weathering resistance. Furthermore, under UV irradiation, the luminescence produced by calcein molecules occluded in gypsum crystals formed upon nano-bassanite hydration allows the easy identification of the newly deposited consolidant within the treated gypsum plaster without altering the substrate\'s appearance.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

公众号