微生物诱导矿化修复阿尔寨石窟红砂岩壁面酥碱病害试验研究

阿尔寨石窟寺是内蒙古地区规模最大且保存最为完整的石窟寺建筑群,其蕴含了珍贵的关于历史、宗教、科学、文化的艺术价值,被誉为“草原上的敦煌”。由于当地典型的沙旱寒区气候特征,酥碱成为石窟壁面最为严重的病害之一,目前阿尔寨石窟正处于保护阶段,因此通过室内对病害进行模拟和研究尤为重要。本研究通过微生物诱导碳酸钙沉淀(MICP)技术,对以红砂岩风化土为基质的壁面的酥碱病害进行修复,通过激光粒度分析了病害前后土颗粒粒径的变化,提出酥碱高度、酥粉体积、盐壳厚度的量化指标用以评价病害的发展程度。基于微生物矿化技术生成矿化覆膜对病害进行抑制,推荐使用微生物菌液浓度OD₆₀₀大于1.5的具有耐盐碱性能的矿化菌株,修复后酥碱高度下降幅度大于20%,酥粉体积下降幅度大于30%,盐壳厚度下降幅度大于25%。研究成果对生物矿化技术应用于红砂岩石窟壁面的酥碱病害的修复进行试验验证和可行性评估,为绿色生态环保的岩壁病害修复与加固技术的推广应用进行科学预研。     

泗阳汉墓埋藏环境中细菌的分析与检测

木质物在埋藏环境中不可避免地会受到细菌的侵害,细菌可以对木材的化学成分及超微结构造成很大的影响。本研究采用羧甲基纤维素钠(CMC)改良培养基平板法对泗阳汉墓埋藏环境中的土样及木样中的好氧纤维素分解菌、厌氧纤维素分解菌进行了筛选和纯化;采用CMC培养基平板稀释法对纤维素分解菌数量进行了测定;采用牛肉膏蛋白胨培养基法对优势菌株进行活化,并对其中的16株进行了鉴定。鉴定结果表明泗阳汉墓中的细菌种类主要有奥斯陆莫拉菌、丁香假单胞菌、自养水螺菌、肠杆菌属、魔芋食酸菌、过滤弧菌、假单胞菌等。细胞的形态主要有短杆、球形、杆状等。研究埋藏环境中土样及木样中细菌的种类、数量、分布等可以对木材的劣化机理研究提供科学的分析,为今后的物保护工作提供理论和实践上的指导。     

甘肃泾川出土5件佛教造像彩绘分析及相关研究

运用显微观察、荧光拍照、偏光显微镜、X射线荧光光谱、X射线衍射及扫描电镜能谱分析手段,对#87北魏造像碑、#99隋代佛头、#54宋代残破佛头和2件泥塑佛像残块表面彩绘进行研究。结果显示,北魏和隋代造像红色为朱砂,绿色为石绿,白色为方解石;隋代造像面部肉色为硫酸铅和朱砂的混合物,眼黑为炭黑;宋代造像表面红色为铁红,白色为方解石;泥塑残块#1表面蓝色为石青和石绿的混合物,#2表面为朱砂,判断其制作年代不晚于唐代中期。白灰层主要成分为碳酸钙,并具有亮白色荧光反应,与碳酸钙粉末混合有机胶制成白灰层的荧光反应一致,判断古代样品白灰层中可能存在有机胶结质。在元素分析过程中,铅(Pb)一直存在,而在物相分析中并没有发现Pb的化合物。同样问题在早期关中出土墓葬壁画分析中同样存在,是否与彩绘工艺本身有关,值得引起关注。     

北齐徐显秀墓壁画颜料的科学分析

为了解徐显秀墓壁画的颜料成分和制作工艺,利用光学显微镜、扫描电子显微镜、拉曼光谱、X射线衍射等方法对墓葬壁画颜料进行了分析和研究。结果表明,颜料均为无机颜料,红色颜料主要有铁红和朱砂;黄色颜料为密陀僧;黑色颜料为炭黑;灰色为碳酸钙和炭黑的混合物;白色颜料有碳酸钙和含砷铅矿物,其中碳酸钙既为地仗层,又做颜料层,另外墓道白灰层则主要为石膏。分析结果为了解北齐时期墓葬壁画颜料的时代和技术特征提供了新的材料。     

劣化石刻表层生物矿化加固材料的探索性研究

许多濒危石质文物表层劣化现象严重。但是,以往使用的表层加固材料很难令人满意,探索新的疏松岩石表层加固材料已是当务之急。由于天然生物矿化物耐候性优越,与基底岩石相容性良好,具有较好的加固作用,本工作依据生物矿化的原理,以不同生物大分子溶液作为有机模板,分别控制草酸钙、磷灰石和碳酸钙过饱和溶液于室温下在疏松岩石仿制样品的表层及孔隙内结晶生长。通过抗压强度、表面硬度和耐水浸泡等试验进行了加固效果评价,以考察仿生物矿化材料对含钙疏松岩石的加固能力。实验结果表明,仿生合成的生物矿化材料均具有一定的加固效果,其中以磷灰石仿生矿化材料的加固强度最大,以硫酸软骨素为模板的加固效果为佳。并且,在考察的3种加固方式中,以"直接混合"的加固强度更好,以"表面渗透"的耐水浸泡能力更强。本工作为开发濒危石质文物表层加固材料提供了新的思路。     

秦陵出土青铜水禽锈体组织结构的初步分析

本研究旨在研究秦始皇帝陵园出土彩绘青铜水禽锈体的结构形貌及其形成原因。采用扫描电镜能谱(SEMEDS)、X射线荧光光谱(XRF)、金相显微分析和离子色谱分析(IC)等多种分析手段,对青铜水禽锈体的组织结构及其埋藏土壤进行了分析检测。结果表明:高湿、火烧、人为破坏的特殊埋藏环境是该批青铜水禽严重矿化的主要原因,而有些矿化严重的部分为稳定的粉状锈蚀物,并非传统意义上的“有害锈”;从组织的微观腐蚀特征来看,铸态枝晶结构的样品α相优先腐蚀;而铸后受热组织则呈晶间腐蚀的特点,腐蚀由晶粒间界向晶粒发展;锈体层状结构的产生与Cu₂O溶解产生空隙,并在合适的环境条件下生成了孔雀石有关。     

甘肃省天水伏羲庙壁画颜料显微分析

为了解甘肃省天水伏羲庙壁画的制作工艺和颜料成分,采用偏光显微镜、显微拉曼光谱和扫描电子显微镜-能潜分析对6个样品进行了分析。结果表明,所使用的颜料为矿物质颜料,多为绿,白、红、蓝色等。其绿色颜料为人造碱式氯化铜,白色颜料碳酸钙,红色为朱砂和铅丹,蓝色颜料为青金石。     

国家公园游憩舒适性的探索性研究——基于生理-心理-精神-社会动态模型（BP2S）新视角

游憩舒适性对国家公园游憩文化生态系统服务价值实现和游憩体验质量提升具有重要影响。文章以武夷山国家公园为研究对象,采用扎根理论和网络文本分析方法探索游憩舒适性的定义、结构维度及其生成机理。研究结果表明：（1）国家公园游憩舒适性定义为国家公园游憩舒适物与游憩体验共同作用下通过游憩者主观感受生理、心理、精神和社会的非物质性惠益,并对游憩文化生态系统服务功能做出质量反馈,包含4个核心范畴、12个主范畴和38个附属范畴;（2）游憩舒适物由自然舒适物、人文舒适物、服务舒适物和氛围舒适物4个要素构成,是国家公园游憩舒适性生成的客观驱动因素;（3）基于生理-心理-精神-社会动态模型,构建了国家公园游憩舒适性生成的内在作用机理模型,并强调了身体主体性、沉浸体验性、意义体验性和社会适应性4个主观驱动因素。文章有助于丰富和发展国家公园生态系统文化服务理论,为国家公园游憩空间建设提供理论和实践指导。     

曲的家族

曲,听起来颇为诗意,是中国人为在这片土地上生成的谷物霉菌溺;起的名称,它是在煮熟的谷物基质上发育形成的培养物,也是国人巧夺天工的独特发明。     

长沙走马楼出土饱水竹简的防腐保存

为防止长沙走马楼出土饱水竹简遭受霉菌侵蚀,用观察不同防毒灭菌剂在不同培养基上杀灭和抑制霉菌效果的方法,筛选出菌毒清、霉敌、新洁尔灭和异噻唑啉酮四种防毒灭菌剂。实验结果表明,它们杀灭、抑制霉菌的生长繁殖效果显,有效期长,对物安全,用量少,产品易得,对水中的霉菌和细菌有很好的抑制和杀灭作用,均可作为饱水竹简和漆木器的杀菌、防毒用剂。     

Preparation of a new calcite layer from calcium glycolate for the conservation of sulfated limestone artifacts

A novel preparation method of calcite layer was explored for the conservation purpose of the surface sulfation limestone artifacts. In this method, the alcoholic solution of calcium glycolate was used as a precursor of calcite layer. After application on the surface of gypsum crust on limestone by spraying, calcium glycolate can combine with the carbon dioxide spontaneously and form a compact calcite layer. The obtained calcite layer can act as a shelter and can prevent the gypsum crust from the dissolution damage of the natural precipitation. The protective properties of the calcite layer were investigated by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS), X-ray diffraction (XRD), infrared spectroscopy (FTIR), water erosion resistance, water absorption, colour difference, surface strength, and hardness test. The results revealed that the water erosion resistance, surface strength, and hardness of the treated sample were increased remarkably. Meanwhile, the intrinsic physical properties such as porosity, capillary absorption, and appearance were not affected obviously, indicating a good compatibility of the proposed protection method.     

Fracture-fill calcite as a record of microbial methanogenesis and fluid migration: a case study from the Devonian Antrim Shale, Michigan Basin

The Devonian Antrim Shale is an organic‐rich, naturally fractured black shale in the Michigan Basin that serves as both a source and reservoir for natural gas. A well‐developed network of major, through‐going vertical fractures controls reservoir‐scale permeability in the Antrim Shale. Many fractures are open, but some are partially sealed by calcite cements that retain isotopic evidence of widespread microbial methanogenesis. Fracture filling calcite displays an unusually broad spectrum of δ¹³C values (+34 to ?41‰ PDB), suggesting that both aerobic and anaerobic bacterial processes were active in the reservoir. Calcites with high δ¹³C values (>+15‰) record cementation of fractures from dissolved inorganic carbon (DIC) generated during bacterial methanogenesis. Calcites with low δ¹³C values (13C values between ?10 and ?30‰ can be attributed to variable organic matter oxidation pathways, methane oxidation, and carbonate rock buffering. Identification of ¹³C‐rich calcite provides unambiguous evidence of biogenic methane generation and may be used to identify gas deposits in other sedimentary basins. It is likely that repeated glacial advances and retreats exposed the Antrim Shale at the basin margin, enhanced meteoric recharge into the shallow part of the fractured reservoir, and initiated multiple episodes of bacterial methanogenesis and methanotrophic activity that were recorded in fracture‐fill cements. The δ¹⁸O values in both formation waters and calcite cements increase with depth in the basin (?12 to ?4‰ SMOW, and +21 to +27‰ PDB, respectively). Most fracture‐fill cements from outcrop samples have δ¹³C values between ?41 and ?15‰ PDB. In contrast, most cement in cores have δ¹³C values between +15 and +34‰ PDB. Radiocarbon and ²³⁰Th dating of fracture‐fill calcite indicates that the calcite formed between 33 and 390 ka, well within the Pleistocene Epoch.     

Differentiating between anthropogenic calcite in plaster,ash and natural calcite using infrared spectroscopy: implications in archaeology

Infrared spectroscopy provides information not only on the type of calcium carbonate polymorph, but also on the extent of atomic order. In calcite, three major infrared absorption peaks are identified: ν₃, ν₂, and ν₄. It was shown that the ratio between ν₂ and ν₄ bands reflects the order of the calcite crystal structure. In this paper we analyse this ratio in geologically formed calcites, archaeological plasters, modern plasters and experimentally prepared plasters. For the geological calcite, the values of the ν₂/ν₄ ratio are around 3, whereas for the experimentally prepared plasters, the values are around 6.5. The ν₂/ν₄ ratio for archaeological plasters varies from 3 to 6. This shows that a high ratio is indicative of disorder in the crystal, and implies that the calcite was formed from calcium oxide at high temperatures. It also implies that this disorder can be preserved for at least 14,000 years. The ν₂/ν₄ ratio of calcite from archaeological sites can thus be used to differentiate between anthropogenic calcite, such as in plaster, mortar and wood ash, from geogenic calcite, such as in limestone. The ratio may also be used to identify plaster or ash that still retains its original crystals and therefore carbon-14 content.     

AN 8500‐YEAR‐OLD BLADDER STONE FROM UZZO CAVE (TRAPANI): FOURIER TRANSFORM–INFRARED SPECTROSCOPY ANALYSIS*

A calcium carbonate (calcite) bladder calculus was found in the pelvis of an adult female buried in a Mesolithic cave‐tomb on the coast of Sicily; it was dated by ¹⁴ C to around 6500 bc . Its chemical composition, which was not known before, was determined by means of Fourier transform–infared microspectroscopy (FT–IR–M) using the high‐pressure diamond cell, a device that makes it possible to analyse a small amount of the sample (1–2 µg). In this way, the analysis of all the laminations of the calculus was performed without destroying the sample. Although calcite was the main component, carbonate apatite was also detected in the nucleus and in a more external layer.     

Salt weathering of sandstone at the Angkor monuments,Cambodia: identification of the origins of salts using sulfur and strontium isotopes

The Angkor monuments in northwestern Cambodia, which are primarily made of sandstone, are suffering from deterioration due to salt weathering. In order to elucidate the sources of the salts and salt weathering process, this paper analyzed bulk chemical compositions and S (sulfur) and Sr (strontium) isotopic ratios for the salts and surrounding environmental materials. At places where bats inhabit the structures, various kinds of sulfate and phosphate salts are formed on the surface of the sandstone. The results of the analysis demonstrate that the S and P (phosphorus) components in the salts are primarily derived from bat guano. Moreover, Ca (calcium), which is the major element in the salts, is suggested to be derived from both bat guano and the sandstone. The isotopic data strongly suggests that bat guano is related to salt weathering. Removal of these animal excrements is essential for future conservation of these monuments. On the other hand, exfoliation of sandstone commonly occurs due to crystallization of calcite (CaCO₃) on platform surfaces of pyramid-type monuments. A large amount of Ca in calcite is suggested to be derived from calcite cement of the building sandstone.     

STUDY ON THE PIGMENTS IN THE CRUCIFORM GALLERY OF ANGKOR WAT,CAMBODIA

In the cruciform gallery of Angkor Wat in Cambodia, red, orange, white and black pigments were widely painted on the surfaces of pillars, walls and friezes. The application sequence of the pigments is different from area to area. The following substances were confirmed from the pigments: hematite (laterite), minium, calcium oxalate hydrates (whewellite and weddellite), Pb–Cl compounds (cotunnite, laurionite and blixite), calcium phosphates (whitlockite), gypsum, hydrocerussite, calcite, anglesite, lead dioxide, azurite and carbon black. The orange pigment (minium) underlies the red pigment (hematite). The former may have been applied at the time of the foundation (the Angkor Wat style period), and the latter in the Bayon style period or later, but mainly before the early 17th century of the current era.     

Oxalate Patinas on Stone Monuments in the Venetian Lagoon: Characterization and Origin

Calcium oxalate patinas have been sampled on architectural elements of two ancient churches located on Torcello Island (Venetian Lagoon) and subsequently analyzed. The site had been selected presenting patinas of exceptional amount and thickness, elsewhere generally found as thin alteration layers covering stone surfaces or within black crusts on monuments in urban environments. Optical and mineralogical analyses suggest that these patinas are not the result of a simple deposition process, but originate as surface “transformations” of the substrate, and are mainly composed of dihydrate calcium oxalate (weddellite) and gypsum. Among the experimental techniques, isotope analyses (C and S) have been specifically carried out aiming at achieving a better understanding of their origin and possible causes of formation. The observed carbon isotopic fingerprint reveals in fact a strong biological fractionation recorded in the oxalate patina (δ¹³C ranging from ?22.3‰ to ?28.0‰), almost exclusively attributable to C3 pathway photosynthesis processes. Slightly negative sulfur isotope ratio values seem to be inversely correlated with patina exposure to atmospheric agents and pollutants. The results obtained prove that calcium oxalate originates from a biomineralization process induced by lichen colonization in specific environmental conditions.     

细菌纤维素对木质文物修复的初步探索

为研究细菌纤维素对木质文物的修复效果,首先检测了产纤维素的醋杆菌Acetobactersp．PDA静置培养时的生长,然后将其与小块的饱水木材一起静置培养,通过测定木块处理前后的湿重及扫描电镜观察,结果显示细菌纤维素对木质文物有一定的修复作用。     

传统建筑泥灰类加固材料的性能研究与机理探讨

人们已经发现一些古建筑所使用的传统材料具有较好的加固作用,其耐久性、强度、与建筑本体的和谐、以及与环境的友好等方面都具有突出的优点。但是由于当时科学技术水平的限制,以及天然材料混合物本身的复杂性,这些传统材料的加固机理一直未被人们充分认识。为了利用和发展传统材料的优势并为古建筑和文物保护服务,本工作选择最具中国特色的以石灰等无机材料为基料,以糯米浆和蛋清等天然生物材料为配料的古代建筑灰浆配方和三合土配方,开展了一系列加固性能研究,并且结合现代SEM和XRD分析仪器,对一些典型的样品进行了微观结构和形貌分析。结果发现,这些古代配方具有现代复合材料的某些特点,即通过无机/有机相互协同的效应,达到了较好的加固效果;重要的是发现糯米浆具有一定的生物矿化的模板作用,即糯米浆的生物大分子对碳酸钙的结晶和生长起到了调控作用,使方解石结晶体的大小和形貌具有一定程度的有序性。本研究为传统材料进一步科学地应用于古建筑和石质文物的修复加固提供了新的思路。     

Red calcite: an indicator of paleo‐karst systems associated with bauxitic unconformities

A unique red calcite generation, which fills fractures/cavities, is hosted by Mesozoic carbonates in the Transdanubian Range, Hungary. Solid inclusions are located along growth zones of calcite. Hematite, the most abundant solid inclusion, gives the red colour of it. Outcrop‐scale geometry, mineralogical features and detrital mineral assemblage (hematite, gibbsite, goethite, kaolinite, smectite, illite, Cr‐spinel, monazite, xenotime, zircon, apatite and Ti‐oxide) of calcite precipitates suggest strong correlation between the calcite and nearby karst bauxite deposits. Fluid inclusion petrography and microthermometry (T < 50°C; salinity from 0 to 0.17 NaCl eq. w%) of primary fluid inclusions, and the stable isotope trend of the calcite, following the meteoric water line, clearly indicate vadose and phreatic meteoric origin in a near‐surface karst system. The late Cretaceous to mid‐Eocene unconformity‐related cavity‐filling deposits occur close to the surface; indicating that the most recent Quaternary exhumation re‐exposed those surfaces that existed at the time of calcite mineralization. Thus, red calcite precipitates are interpreted as being speleothems, vestiges of the subterranean part of the pre‐Middle Eocene karst. The infiltrated, fine bauxite particles enclosed by the calcite are the witnesses of the once areally extensive pre‐Middle Eocene bauxitic blanket that became partially eroded by the time of the deposition of the cover beds. Red calcite when found in core samples may provide good evidence on bauxite formation associated with the overlying unconformity, even if it was later removed by erosion. Therefore, presence or absence of red calcite may be used as distinguishing criteria between karst episodes with or without bauxite formation.