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1.
木质及纸质材料是博物馆环境空气中有机酸最主要的来源,所释放出的挥发性有机酸包含甲酸、乙酸、丙酸、丁酸、戊酸等短链脂肪酸。这些有机酸气体会导致青铜文物的腐蚀,铅质器物表面的风化,珐琅、陶器的腐蚀脆化,丝织品纤维的劣化,纸张寿命的缩短等。为此,本研究建立了一种基于离子色谱同时测定博物馆环境空气中甲酸、乙酸、丙酸、丁酸和戊酸等5种挥发性有机酸浓度的方法。以超纯水作为吸收液,吸收液体积为10 mL,采集流量为400 mL/min,主动采样法采集博物馆环境空气样品。采用5 mmol/L KOH淋洗液等度洗脱,在9 min内可同时测定五种挥发性有机酸的浓度。结果表明,在0.05~0.50 μg/mL的线性范围内,甲酸根、乙酸根、丙酸根、丁酸根、戊酸根的标准曲线的相关系数均高于0.995,检出限为0.001~0.009 μg/mL,定量限为0.004~0.030 μg/mL;五种有机酸根的加标回收率为91.4%~107.4%。库房A中检测到的甲酸、乙酸的浓度范围分别为36.40~85.44 μg/m3,274.42~312.11 μg/m3;库房B中检测到的甲酸、乙酸、丙酸的浓度范围分别为18.66~ 34.00μg/m3,123.53~152.55 μg/m3,15.80~24.48 μg/m3。该方法具有采样简单,样品无需前处理,检测时间短,成本低等优点,适用于博物馆的日常检测工作。  相似文献   

2.
大气颗粒物是潜在威胁遗址与文物的一种大气污染物,颗粒物沉降或吸附后覆盖文物表面细节,降低其审美价值,并带来进一步的物理或化学侵蚀。通过分析莫高窟开放洞窟(16窟、257窟)、非开放洞窟(320洞窟)和窟外大气中各粒径颗粒物(总悬浮颗粒物TSP、粗颗粒物PM10和细颗粒物PM2.5)背景和典型沙尘天气质量浓度及其碳组分和水溶性无机离子组分含量,获得文物保存环境中大气颗粒物的质量浓度及化学组成。各观测季节内,非沙尘天气窟内TSP质量浓度介于48.4~60.0μg/m3,PM10质量浓度介于13.3~61.3μg/m3,PM2.5质量浓度介于9.9~59.2 μg/m3。洞窟是否向公众开放对窟内颗粒物浓度水平和组成的影响不显著,开放和非开放洞窟颗粒物质量浓度的I/O比值多小于1,显示窟内颗粒物主要源于室外。窟内颗粒物化学组成中,地壳源矿物尘多占据主导地位,在沙尘频发的春季占比介于53.0%至80.7%之间,冬季占比介于17.1%~44.0%。其他化学组分中,细颗粒PM2.5中碳组分和总水溶性无机离子含量占比明显高于TSP和PM10。冬季窟内PM2.5质量浓度低于春季,但碳组分和无机离子浓度值和含量占比均高于春季(除去春季16洞窟),冬季碳组分和无机离子含量占比高达60%,其中酸性组分含量占比和可达30%。对莫高窟大气颗粒物的控制不能忽视细颗粒浓度及其化学组成的潜在危害。  相似文献   

3.
文物保存微环境空气氮氧化物集成净化技术研究   总被引:2,自引:2,他引:0  
为研究文物保存微环境中的集成净化技术,联合采用光催化预处理和竹炭吸附技术净化低浓度的氮氧化物.研究了组合方式在不同光源下的净化效果,同时探讨了湿度对低浓度氮氧化物净化效果的影响.结果表明:在采用恰当的组合情况下,紫外线照射和可见光照射下,净化结果相差不大,最佳组合为光催化+竹炭+4A分子筛+竹炭的组合,NO和NO2的出口浓度分别可降至1.98μg/m3和1.80μg/m3;而相对湿度增加,处理效果降低,但在相对湿度为60%情况下,仍可较长时间内稳定运行,保持出口NOx在4ng/g以下.综合实验结果,光催化联合竹炭吸附集成技术净化低浓度的氮氧化物效果良好,为今后文物保存微环境中的实际应用提供科学依据.  相似文献   

4.
NOx是文物保存环境的一类重要的污染物,近期采用资源丰富、价格便宜的竹材及竹炭作为吸附剂去除污染物成为热点.本工作采用低温竹炭净化低氮氧化物,并对效果的影响因素进行了探讨,使用扫描电镜对低温竹炭表面形态进行了研究.研究表明,低温竹炭处理浓度在133~457 μg/m3NO时,处理效率可以达到84%~94%,处理浓度在82~453 μg/m3NO2时,处理效率可以达到93.3%~97.7%.当NO和NO2同时存在时,NOx在500 μg/m3时(NO:NO2=2:1),NO的处理效果下降,仅能达到44.7%,但是NO2的处理效果变化不大,仍可以达到98%.  相似文献   

5.
空气中的SO2气体对丝织品文物有一定的危害作用。课题分别试验了各种丝织品试样在50μ mol/mol的SO2气体下不同时间的影响变化。通过色差分析,红外分析,氨基酸分析及XRD分析对丝织品进行表征,得到了40℃下50天的干热老化丝织品试样在50μ mol/mol的SO2气体下,随着试验时间的延长,其色差变化最大。经SO2气体处理的丝织品试样的氨基酸成分发生改变,结晶度也变大,老化程度加大。本研究结果可为保存和保护丝织品文物提供依据。  相似文献   

6.
氮氧化物(NOx)是环境中的重要污染物,是文物保存环境的重大威胁,不仅其本身会对文物产生严重危害,而且与其他污染物如硫氧化物和有机酸耦合会加剧侵蚀。为此,本研究采用光催化预处理与生物质吸附集成技术净化文物保存微环境空气中低浓度的氮氧化物。实验结果表明:直接使用竹屑、杉木屑、落叶松、稻壳和稻糠生物质可去除NOx;在520℃下炭化的竹炭对NOx去除率可达75%。NOx的光催化效率随流速升高而降低,当NOx中混有有机酸时集成净化效率会出现波动。对光催化和吸附的不同组合进行了比较,最优组合可使NO和NO2浓度分别降至1.98μg/m3和1.80μg/m3。  相似文献   

7.
使用XRD方法分析了1%BTA+5%H2O2清洗剂对古青铜上氯化亚铜相的清洗效果.给出了在BTA存在的条件下,使用PIXE、MA分析氯离子的结果.用选择性电极法,分析了在碳酸根存在的条件下的氯离子浓度.证明了1%BTA+5%H2O2[1]能有效地清洗青铜中的氯化亚铜和氯离子;也证明了在适当提高温度的条件下,有利于倍半碳酸钠清洗青铜中的氯离子。  相似文献   

8.
不同于新出土青铜器上的锈蚀物,博物馆藏金属器物上经常可见浅蓝色铜的锈蚀物。为辨别和探析其成因,通过采用扫描电子显微镜-能谱仪(SEM-EDX)、X射线衍射仪(XRD)和激光拉曼光谱仪(Raman)进行元素成分和物相综合分析,发现其为铜的有机盐。这些有机盐包括简单(或碱式)的甲酸铜和乙酸铜,也包括复杂的含有钠离子和碳酸根的乙酸铜NaCu(CO3)(CH3CO2)、含有钠离子和氧离子的水合甲酸铜Cu4Na4O(HCOO)8(OH)2·4H2O。这种浅蓝色铜的有机盐形成根源主要有两种:储存或展览环境的不当;用于除锈的化学试剂的残留。要杜绝这类锈蚀物的形成需要确保储存和展览器物的环境低湿度且无有机酸释放材料的存在。对经过化学处理的器物应确保将化学试剂清理干净且无任何残留以绝后患。对复合材料器物的处理更应谨慎,因为对不同材质的处理和保存环境要求不一样,要个例对待。  相似文献   

9.
中国古代黑镜通常都有厚约100μm由铜锡合金相和SnO2组成的表面层[1,2]。利用改进了的K值法[3,4],测试分析铜镜表面层的粉末样品,可得到物相的定量数值。本文以一块普通唐镜为例,讨论了结果的可靠性。  相似文献   

10.
陕西境内遗址出土后短时间内表面产生白色物质CaSO42H2O是非常普遍的现象。本研究利用土柱模拟遗址出土后表面产生CaSO42H2O的过程,通过监测土柱中土壤的湿度、含盐量及离子变化综合分析CaSO42H2O产生的原因,研究结果表明遗址出土后形成了新的界面层,在蒸发的作用下,地下水沿土壤孔隙向上迁移,同时将可溶盐带入土壤中,表面的可溶盐含量逐渐增大,达到峰值后不再增加,实验后测得表面土壤中的Ca2+和SO2-4是原始土壤的数十倍,说明遗址表面产生CaSO42H2O是水盐运移的结果。本研究可为遗址出土后预防CaSO42H2O的产生提供依据。  相似文献   

11.
The Knowledge of Debt: Law, Media Technique, and Everyday Experience in Liberal Capitalism. Performing an object such as ‘the economy’ hinges on practices of formatting knowledge. The article proposes to look at such instituting moments in connection with social conflicts over the legitimate rules of exchange. This is exemplified by way of recounting the story of the codification of Swiss bankruptcy law in 1889. In order to homogenize the legal procedures of debt collection and bankruptcy, two subject categories were instituted: ‘merchants’ and ‘non-merchants’. These different categories were thought to account for the diverging temporalities and spaces of credit exchange in everyday economic life. The introduction of the commercial register, a media-technical apparatus, enabled a formal distinction between ‘merchants’ and ‘non-merchants’. However, this boundary was contested and proved to be porose.  相似文献   

12.
Shells of two species of freshwater bivalve (Unio willcocksi Bullen Newton and Etheria elliptica Lamarck) from the predynastic Gerzean (Nagada II) Decorated Tomb at Hierakonpolis, Egypt have given dates of 5000±90 bp for the tomb, and 12,900±120 bp for an episode of Nile terrace accumulation (correlated here with the Sahaba-Darau aggradation event). The archaeological and geological significance of these results is discussed, together with an outline of problems associated with radiocarbon dating of shell. Comparisons are made with the few other radiocarbon dates available for the Predynastic period in Egypt and possible reasons for the presence of shells in the tomb are considered.  相似文献   

13.
Work initiated purely as a dating project in support of a craniometric and morphological investigation of domestic dogs from early Peru has proved to have much wider implications. The stable carbon isotoperatios (13C/12C) of hair samples from ten dogs show that maize formed a significant part of their diet. Radiocarbon dates for these remains have confirmed that they belong to the period well after the cultivation of maize was first established. Stable carbon isotope measurements can thus be used to test for the presence of maize as a dietary constituent at earlier sites even where there is otherwise only indirect evidence for its cultivation. Collagen from animal or human bone is a suitable alternative to hair for this purpose and the method has been successfully applied to collagen dating to c. 3000 BC from the Valdivia culture site of Real Alto, Ecuador, as well as to a series of early Peruvian dogs.  相似文献   

14.
Abstract

This paper is informed by Furse’s practice as a theatre maker in two fields of output that are connected by two factors: first, the presence of the woman patient — hysteric/subfertile respectively — within the clinical gaze; second, the significance of the womb to each pathology. In the treatment of each (explored in Furse’s theatre), lens based technologies play their part, whilst the cultural and medical can be seen to have overlapped to produce specific meaning with regard to Her body and its spectacularity. The article presents an overview of some of the key issues in precisely how the woman’s body becomes spectacular within this prosthetic medical gaze and how the medical — and theatrically designed spaces to represent these — become meaningful and potent proxemics that in turn inform medical/ theatrical spectatorship. Overarching nineteenth-century protocols at the Salpêtrière Hospital in Paris (where Furse’s Augustine (Big Hysteria) is set) to contemporary imaging technologies used in the treatment of subfertility with Assisted Reproduction Technologies (the topic of her Art of A.R.T. projects), it examines the way in which photography develops through cinema to X-Ray, ultrasound and then 3D/4D ultrasound to ‘capture’ the woman’s body in ways by which she becomes muted and exposed. These occular technologies that extend the gaze, first to an exterior subject and then, eventually, traversing the flesh without knife, lend specific performativity to the ‘patient’ women, within the context of hysterias and reproductive impairments respectively. Finally, issues of suspension of disbelief are addressed. The spectator’s faith in the screen-based image of Her spectacular body is interrupted in Furse’s work, which is also keenly interested in the effect of such imagery on the woman’s sense of Self. The historical and cultural leaps in this article argue that there is indeed a trajectory through the history of medical imaging since the first application of photography to anatomy to the more advanced scoping technologies of medical imaging today, and that in each era, the production of these images remain fraught with cultural implications.  相似文献   

15.
Alexander the Great died in 323 B.C. from an unknown cause. Physical depictions of this historical figure reveal the likelihood of a cervical scoliotic deformity. This is substantiated with the medical history and is correlated with his untimely death. For the first time, it is concluded that Alexander’s death may have ensued from the sequelae of a congenital scoliotic syndrome.  相似文献   

16.
The later post-glacial history of a valley in the chalk escarpment near Brook, Kent, is described, based on molluscan stratigraphy, archaeological evidence and radio-carbon dating. Differences in size and colour banding, respectively, of fossil and living representatives of two species of land snails, Pomatias elegans (Müller) and Cepaea nemoralis (L.), are correlated with climatic change during the post-glacial period. The problems of the use of fossil shells of these species as samples for radiocarbon dating are discussed.  相似文献   

17.
18.
A noted British economic analyst and observer of current developments in Russia compares that country's emerging economy with those of China, India, eight other populous emerging states, and the United States. The focus of the comparison is on the extent to which these countries exhibit potential for functioning as "knowledge-based" economies. The four pillars of such economies are identified as: (1) an educated and skilled population; (2) a network of R&D institutions; (3) a dynamic information infrastructure; and (4) a regime promoting the development of knowledge. Journal of Economic Literature, Classification Numbers: L86, O30, O57. 1 figure, 19 tables, 91 references.  相似文献   

19.
A Singapore-based economic geographer explores and analyzes the spatially uneven evolution of the Internet industry in China, arguing that the country's immense regional disparity in the provision of Internet services is best explained by the interplay of place- and path-dependence. The author demonstrates how the highly uneven regional endowments in relevant industrial and entrepreneurial resources have led to the substantial and persistent regional imbalance within China's emerging "new economy." His initial survey of the country's 100 leading Internet content providers (firms), identified from a listing of ca. 11,700 commercial websites, is selectively augmented to reflect an increase of over 70 million Internet users in 2007, reaching a total of 253 million in June 2008, and thus overtaking the United States as the world's largest Internet market. Journal of Economic Literature, Classification Numbers: L10, L86, O30. 6 figures, 1 table, 53 references.  相似文献   

20.
This paper discusses the 1911 International Exposition in Rome and illustrates how this patriotic celebration of the fiftieth anniversary of the Italian Sate utilized symbolic landscapes of architecture and archaeology to promote nationalist sentiments of italianità and romanità centered on the young capital of Rome. Through modern art exhibitions at the Valle Giulia, scientific conferences at the Castel Sant’Angelo, archaeological exhibits on the Roman Empire in the Baths of Diocletian, and regional Italian pavilions in the Piazza d’Armi, exposition officials offered a complex representation of Italian national identity that was modern yet ancient, cosmopolitan yet bucolic, European yet regional, and imperial yet developing.  相似文献   

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