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1.
本文报道贵州省红土洞史前遗址出土的石制品,共有56件,包括石锤(7件)、石核(7件)、石片(13件)、石器(29件)等类型。石器类型简单,只有砍砸器、刮削器、盘状器3种。石器尺寸相对穿洞出土的石器大,石器修理较细致,器形精美。  相似文献   

2.
陆家渠地点发现于2019年汶、泗河流域旧石器时代专项调查过程中,共发现石制品48件。采集品原料均系脉石英,来源于附近砂岩山体。剥片技术分为锤击、砸击两种。石制品类型包括石核、石片及石器等。尺寸以小型为主,中型、微型比例甚小。石器类型简单,可辨识刮削器及雕刻器两种。在泰安市宁阳县旧石器专项调查中发现了包括陆家渠地点在内的26处旧石器时代地点,文化时代应属旧石器时代晚期,技术传统分为小石器及细石器两种类型。这些发现扩大了宁阳县旧石器时代遗存的分布范围,也丰富了山东省细石器遗存的文化内涵。  相似文献   

3.
根据微机电算分析碎石器结构参数和工作参数的变化对碎石器工作性能的影响,揭示结构参数和工作参数对碎石器性能影响的规律,并得出增加油压、前后缸面积差、冲击行程和活塞质量均可增加单次冲击能量;减小冲击行程、活塞质量可增加冲击频率;增大活塞前后缸面积差可提高冲击效率等相应的结论,对于提高碎石器的设计水平,避免设计的盲目性,缩短研制周期等具有重要作用  相似文献   

4.
本文从词意和力学角度对欹器和半坡尖底陶罐进行研究,认为半坡尖底陶罐是欹器的可能性很小;另外对欹器的构造进行了设想。  相似文献   

5.
宣威境内已发现的三个新石器时代洞穴遗址都具有以夹砂灰陶为主,以罐、碗和圈足器为组合,石器中有肩、有段器形等相同的文化特征,并与邻近地区新石器遗址有一定的渊源关系,这些特征表明,宣威新石器文化的族属应为百越民族。  相似文献   

6.
对湖南苗族学生的鼻梁类型、鼻孔形状、下颏类型、额头发际、头发形状等5项头面部形态特征进行了调查,结果显示:苗族多为非凸型鼻梁、宽型鼻孔、突型下颏、无尖型额头发际、直发;除鼻梁类型-下颏类型和下颏类型-头发形状2对性状相关外,其他几项之间不相关.  相似文献   

7.
为探究粗粒组分对加积型红土物源的影响及其环境意义,选取中亚热带洞庭湖周边、鄱阳湖周边、皖浙地区24处加积型红土剖面145个样品,并对其粗粒组分(粒径63μm)开展粗粒矿物磨圆度特征研究,结果表明:1)加积型红土粗粒组分矿物磨圆度与矿物类型有关,棱角状和次棱角状矿物多为长英质碎屑;圆状和次圆状矿物多为赤褐铁矿、钛铁矿等.2)均质红土(HRC)、网纹红土(VRC)的圆度组合类型基本属"尖锥形",且与当地基岩风化物、湖滨风成砂山、河流沉积物样品的圆度组合类型一致;黄棕色土(YB)、网纹黄棕色土(VYB)的圆度组合类型略为复杂.3)以JL剖面为例,加积型红土粗粒组分圆度沿剖面自下而上波动增加,结合以洛川黄土和赣江流域梅江沉积物粗粒组分为端元的物源判别结果,网纹红土粗粒物质来自近源河湖沉积物,而黄棕色土粗粒物质中还混有远源粗颗粒物.  相似文献   

8.
本文记述采自广西和云南的大疣蛛属Macrothele两种:指状大疣蛛Macrothele digitata sp. nov.和敬钊大疣蛛M.jingzhao sp. nov.。指状大疣蛛与湖南大疣蛛M.hunanica ZhuSong, 2000相似,但具以下不同特征:雄蛛触肢器胫节背面具8根壮刺,插入器正面观微弯曲;步足II胫节中部膨大,腹面多刺;雌蛛交配管短,指状。敬钊大疣蛛与颜氏大疣蛛M.yani Xu, YinGriswold, 2002相似,但具以下不同特征:触肢胫节具3根内侧刺;基血囊圆盘状;插入器基部细,端部针状,微弯曲;步足I胫节微弯曲,腹面多刺。  相似文献   

9.
研究了倒金字塔填充型锥尖及正向刻蚀硅尖的制备方法,工艺及封装方法等,并分别测试了这两种场发射尖阵列的电子发射特性,分配表明倒金字塔填充型锥尖适用于制备高频器器件,正向刻蚀的硅尖适用于制备高速开关器件。  相似文献   

10.
分析松辽盆地三肇凹陷不同构造区油藏类型和油水分布规律。结合有效源岩控范围、油源断层控通道、构造样式控部位、沉积演化控层位和单一圈闭控规模等油富集条件分析,提出凹陷不同构造区油聚集机制受控于不同构造背景下的断层与砂体匹配样式,最终建立凹陷分区成藏模式。研究结果表明:源内向斜区主要发育受断层密集带背形构造、油源断层短距离垂向输导和高孔渗分流河道选择性充注匹配控制的窄带状岩性油藏;近源鼻状构造区主要发育受继承性鼻状构造隆起和油源断层近距离侧向输导匹配控制的连片状构造-岩性油藏;源外斜坡区主要发育受断阶带高点、"断-砂"桥连式远距离侧向输导、断层侧向封闭性和岩性上倾尖灭控制的宽带状断层-岩性油藏和岩性上倾尖灭油藏。凹陷分区成藏模式为源内向斜区"T型"运聚成藏模式、近源鼻状构造区"犁式"运聚成藏模式和源外斜坡区"断阶状"运聚成藏模式。  相似文献   

11.
Eight new Palaeolithic open-air sites were identified and 770 stone artefacts were collected from 2009 to 2011 in the Lantian area of the Bahe River valley, central China. Because the famous Homo erectus fossils were unearthed at the Gongwangling and Chenjiawo localities, and more than 30 Palaeolithic open-air sites were investigated in the 1960s in this region, the catchment of Bahe River is regarded as one of the most important hominin sites from the late early Pleistocene to the middle Pleistocene. These eight newly discovered open-air sites are located at the second(n = 6), third(n = 1) or higher terraces(n = 1) of the Bahe River. The Diaozhai section on the second terrace was sampled in detail. Two samples were collected for optically stimulated luminescence dating(OSL). The OSL results suggest that a buried lithic artefact layer at the Diaozhai site spans approximately 70–30 ka. The lithic assemblage analysis suggests that the stone artefacts were made of local pebbles/cobbles such as greywacke, quartz, sandstone and igneous rocks. The main percussion techniques that were used were direct hard hammer percussion and bi-polar techniques. The lithic artefacts comprise hammer stones, cores, flakes, retouched tools and flaking debris. Acheulian-type large cutting tools(LCTs) such as hand-axes, picks and cleavers were indentified in the Lantian region as well. This is the first time Acheulian-type LCTs from the late Pleistocene have been identified in this region. This study distinguishes age gaps between Western world and East Asian Acheulian-type tools.  相似文献   

12.
针对国内薄片烟丝的储存高度不易高于500 mm而导致烟丝储存占地面积大的缺陷,设计一种三层输送皮带机头尾叠加结构的薄片储丝柜,该储丝柜占地面积是原薄片储丝柜占地面积的三分之一,而且储丝柜的烟丝进出柜箱先后有序,先进入,先出柜,保证了卷烟质量。  相似文献   

13.
研究了微波处理、水浴加热、超声处理及高压均质对高温变性豆粕可溶性蛋白含量的影响.通过实验证明微波处理和水浴加热对提高高温变性豆粕氮溶解指数效果明显,并对两种加热处理方式进行了正交L9(34)优化试验.结果表明,微波(700 W)处理在pH 8.0,底物质量分数3%,时间5 min时氮溶解指数达到70.39%;加热处理高温变性豆粕的较佳条件为pH 8.0,反应时间90 min,底物质量分数为1%,其溶液氮溶解指数可达74.81%;但在较高底物质量分数(3%)下,加热处理高温变性豆粕的氮溶解指数只达到63.96%.微波处理后蛋白质的其他功能性要优于酶处理后的,因此微波加热处理高温变性豆粕可有效提高生产效率,有利于实现工业化生产.  相似文献   

14.
胡家营遗址出土的12件战国铁器是研究东周时期铜器文化特征、制作技术及与周边考古学文化相互关系等学术问题的重要资料.为进一步揭示该批铁器包含的科学信息,对其进行了金相组织鉴定、夹杂物分析和碳十四测定.结果显示,14个铁器样品中有6个是韧性铸铁、1个是共晶白口铁、1个是过共晶白口铁、6个是铸铁脱碳制品,包括3个熟铁,1个亚共析钢,1个过共析钢,还有一个样品是外部熟铁,内部过共析钢,且所有样品的制作工艺皆为铸造.碳十四测年数据显示的铁器年代为春秋战国时期.  相似文献   

15.
Nickel-coated graphite flakes/copper (GN/Cu) composites were fabricated by spark plasma sintering with the surface of graphite flakes (GFs) being modified by Ni-P electroless plating. The effects of the phase transition of the amorphous Ni-P plating and of Ni diffusion into the Cu matrix on the densification behavior, interfacial microstructure, and thermal conductivity (TC) of the GN/Cu composites were systematically investigated. The introduction of Ni-P electroless plating efficiently reduced the densification temperature of uncoated GF/Cu composites from 850 to 650℃ and slightly increased the TC of the X-Y basal plane of the GF/Cu composites with 20vol%-30vol% graphite flakes. However, when the graphite flake content was greater than 30vol%, the TC of the GF/Cu composites decreased with the introduction of Ni-P plating as a result of the combined effect of the improved heat-transfer interface with the transition layer, P generated at the interface, and the diffusion of Ni into the matrix. Given the effect of the Ni content on the TC of the Cu matrix and on the interface thermal resistance, a modified effective medium approximation model was used to predict the TC of the prepared GF/Cu composites.  相似文献   

16.
机械加工车间现场工具配送方法及实现   总被引:1,自引:0,他引:1  
围绕机械加工制造车间现场管理的问题,研究并建立了一种新的基于动态配送的加工车间现场生产工具的管理方法,形成了一种符合该方法的生产工具现场动态配送计划。在此基础上建立了加工车间现场生产工具动态配送系统的功能树模型和信息模型,开发了相应的信息系统,实现了将车间现场物流和刀具、工装等加工工具进行动态回收和配送,降低了生产工具的库存,提高了加工生产效率,通过企业的实际运行,取得了良好的应用效果。  相似文献   

17.
传统的降低板材厚度膨胀的方法主要是通过提高施胶量和添加石蜡,或通过热、蒸汽、化学处理等,但往往会增加成本及影响材料的力学性能。板材厚度膨胀的最主要根源是木材的结构和特性以及热压时水分、温度、压力和时间对板材的综合作用。笔研究了在不同的热压条件下,板坯内不同层的薄片刨花的膨胀以及薄片刨花板厚度方向上的膨胀分布。结果表明,在较低的热压温度下,刨花的压缩率和膨胀率呈明显的相关性,而在较高的热压温度下,尽管表层刨花的压缩率较高,但其厚度膨胀率仍小于芯层刨花。为降低木质复合材料的厚度膨胀,建议采用较高的热压温度。  相似文献   

18.
Earliest Homo.     
A Hill  S Ward  A Deino  G Curtis  R Drake 《Nature》1992,355(6362):719-722
The origin of our own genus, Homo, has been tentatively correlated with worldwide climatic cooling documented at about 2.4 Myr (million years). It has also been conjectured that members of Homo made the first stone tools, currently dated at 2.6-2.4 Myr. But fossil specimens clearly attributable to Homo before about 1.9 Myr have been lacking. In 1967 a fossil hominoid temporal bone (KNM-BC1) from the Chemeron Formation of Kenya was described as family Hominidae gen. et sp. indet. Although a surface find, its provenance within site JM85 (BPRP site K002) was established and a stratigraphic section provided indicating the specimen's position. This evidence has been affirmed but the exact age of the fossil was never determined, and the absence of suitable comparative hominid material has precluded a more definitive taxonomic assignment. Here we present 40Ar/39Ar age determinations on material from the hominid site indicating an age of 2.4 Myr. In addition, comparative studies allow us to assign KNM-BC1 to the genus Homo, making it the earliest securely known fossil of our own genus found so far.  相似文献   

19.
纳米晶Fe85Si1Al6Cr8片状颗粒材料微波吸收特性   总被引:1,自引:0,他引:1  
采用快淬工艺和高能球磨处理技术制备了纳米晶FeSiAlCr片状颗粒材料.研究了高能球磨处理工艺对材料微结构、形貌和微波电磁特性的影响。结果表明高能球磨处理使球形粉粒形状扁平化并细化其晶粒,从而使FeSiAlCr颗粒材料的微波磁导率显著提高,介电常数被有效控制.对用该材料制作的涂层吸波性能进行了计算模拟,结果表明在4GHz附近微波段具有良好吸波性能.  相似文献   

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