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11.
Northwest China is known for its Majiayao-style Neolithic painted pottery which has received much praise for its high level of craftsmanship, yet its chain of production, in particular the step of raw material selection, is still poorly understood. To fill this lacuna, the present study explores the raw materials used in producing these wares from a geological and technological perspective. At its core stands the first geoarchaeological survey conducted around the eponymous site of Majiayao which collected 47 samples of raw materials suitable for ceramic production including clay, loess and rocks, which were all analysed macroscopically. A selection was analysed using thin-section petrography, and a subset of the clay and loess samples were subjected to firing experiments. Additionally, three clay samples were analysed by scanning electron microscope with energy-dispersive X-ray spectrometer to understand their composition and behaviour in ceramic production. These were then compared to archaeological ceramics, thus providing insights into raw-material availability and selection that will be of importance not only for research on Majiayao-style pottery but also for later-period ceramics produced in the area. This research shows how an archaeologically informed geological survey can contribute insights into human–environment interaction in early pottery production, especially the interplay between raw-material availability, technological know-how and potters' choices.  相似文献   
12.
为使RZB型钻孔应变仪在千米深井水压的作用下能够正常工作,设计了以陶瓷马达为核心、RS485总线为基础的远程控制机构,用以补偿传感元件的初始位移,从而实现RZB型钻孔应变仪量程的扩展,并在实验室开展了10 MPa水压的模拟实验。结果显示,装有量程扩展系统的传感器在5 MPa处超量程,经量程调节后,在10 MPa处仍能正常工作。  相似文献   
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李治朋  张宇亭  马希磊 《岩土工程技术》2011,25(4):214-216,F0003
首先对膨胀土基本性质做了试验分析,通过天然膨胀土和掺人纤维前后的石灰土的击实试验,得出了掺人少量纤维对石灰土的最优含水率和最大干密度影响很小.通过有荷膨胀率试验,得出了纤维能够抑制石灰土的膨胀性,纤维掺人量在0.05%~0.1%之间时,线膨胀率随纤维掺人量的增多而降低显著,在0.1%~0.2%之间时降低幅度减小.由无侧...  相似文献   
15.
陶瓷釉的矿物学特征研究   总被引:2,自引:0,他引:2  
应用原子吸收光谱(AAS),X射线衍射(XRD)和 电子自旋共振(ESR)方法对工业及民用陶瓷釉进行了研究。实验表明:陶瓷釉的主要化学 成分为Al2O3、SiO2,少量为K2O、Na2O、MgO、CaO和微量的TiO2、Fe2O3 、S等;矿物相有石英、伊利石、方解石、长石、高岭石和滑石等。生釉经不同温度焙烧后 ,无论是化学成分、矿物相、微量杂质元素的价态及含量均发生了变化。讨论了在不同温度下的化学组分、含量、生成矿物相的种类以及杂质离子在矿物内部的电荷转移状态。这些结果对改进陶瓷釉的配方,探索最佳焙烧温度,生产高质量的陶瓷产品,有着实际的指导意义 。  相似文献   
16.
This paper describes the development of a computational model to predict the response of synthetic-fiber ropes under both monotonic and cyclic loads. The model addresses the issue of damage to a rope cross-section and its effect on rope response. Isotropic damage is assumed and is therefore characterized by a scalar quantity known as the damage index. The damage index is used to quantify the amount of deterioration that takes place in a damaged rope throughout its loading history. For the current study, data obtained from static tension tests are used to determine the evolution relationship for the damage index. This relationship is based on the stiffness ratio between experimental data and simulation of rope response without any source of damage and is assumed to be described by an exponential equation. Numerical simulations of damaged rope behavior compare well with experimental results.  相似文献   
17.
吉林省陶粒页岩的开发已有十余年的历史,主要矿石自然类型为白垩系下统嫩江组、青山口组泥岩、粉砂质泥岩,目前已开发利用的矿床主要分布于农安—德惠一带松花江西岸的切割台地,均以零星开采为主,矿石质量各有差异,本文通过对这一带典型矿床地质特征进行对比研究,展望该区陶粒页岩矿开发前景。  相似文献   
18.
倪文  邹一民 《地质论评》1998,44(1):71-76
山东焦家金矿是中国最大的金矿之一。该金矿尾矿化学成分接近于常见商品玻化砖的化学成分,其矿物组成以石英及长石为主,接受于常见面商品玻化砖的配料,实验表明,以80%尾矿加20%高可塑怀粘土民的试样,其最佳煅烧温度为1150℃,吸水率〈0.2%的烧成温度的可变化范围是30℃,板状试样经煅烧后不变形,不开裂,抗压强度可达295MPa,颜色美观,光泽度等达到了普通商品玻化砖的水平。  相似文献   
19.
Changes in tissue structure, rheological properties and water content of raw and heated sea cucumber meat were studied. Sea cucumber Stichopus japonicus was heated at 25°C , 70°C and 100°C water for 5 min. The structural changes were observed using a light microscope and the rheological parameters (rupture strength, adhesive strength and deformation) determined using a texture meter. Microscopic photograph revealed that the structural change of heated meat was greater than that of raw meat. The rupture strength, adhesive strength and deformation of raw meat were smaller than those of the heated meat. Meanwhile, rheological parameters showed positive correlation with heating temperature. These changes are mainly caused by thermal denaturation and gelatinization of collagen during heating. These changes were also evidenced in observations using a light microscope and differential scanning calorimetry.  相似文献   
20.
非对称天然沸石陶瓷膜的制备及其性能表征   总被引:1,自引:0,他引:1  
利用天然沸石为主要原料,制备出具有过滤功能和重金属离子吸附功能的天然沸石非对称陶瓷膜。非对称膜中支撑体、中间层膜和顶层膜的平均孔径分别为6.6μm、0.6μm和0.1μm。非对称膜单位压力降(1 MPa)下的氮气通量和水通量分别为:24.69×103m3/(m2h)和1.87×103m3/(m2h);对重金属离子(铅离子)吸附交换能力为7.13 mg/g。  相似文献   
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