自然

This dissertation has six chapters, and the structure is in the following: The first chapter is about the background of agriculture. This chapter analyzes the influence which nature makes to agriculture, and indicates Mediterranean climate and natural situation are favor of the growth and distribution of agriculture. And with the effect of Etruscans and the opinion of physiocracy, Romans inevitably attach importance to agriculture.

本文共分六章，基本框架大致如次：第一章农业发展条件：本章重在分析自然地理对农业生产的影响，指出罗马所拥有的地中海气候及地形复杂、土壤肥沃等自然条件，有利于各种农作物的生长和分布；同时受伊达拉里亚人的影响以及传统上罗马人重农轻商的农业思想束缚，农业生产不可避免地受到人们的重视。

The Natural History Museum, an integral part of the Institute, was founded at the same time under the original name of Physiographic Museum.

同年建立的自然历史博物馆是该所的一部分，当时它的名称是自然地理博物馆。

Based on natural and social situation of Hebei province, an index system was built in this paper, involving in indexes in physiographic conditions, present level of water-saving and its potential and social economy.

根据河北省的自然与社会情况，选取自然地理条件、现状节水水平与潜在的节水效益、社会经济条件等方面的指标组成农业节水区划的分区指标体系。

The ammonia was evaporated under decreasing pressure, and the precipitate was filtered off and the liquid was poured into hot saturated picric acid solution to get picrate with a yield of 85.0%. The optimum process starting from imidazole-4,5-dicarboxylic acid was: imidazole-4,5-dicarboxylic acid in acetic anhydride was refluxed to get imidazole-4-carboxylic acid, and the product was esterification in ethanol with a catalyzer of concentrated sulfuric acid to get ethyl imidazole-4-carboxylate, at last the compound above was reduced by LiAlH4 in ether at room temperature to get the target compound, the total yield of this route was 49.6%.

以4，5-二羧酸咪唑为原料的较佳工艺：1 脱羧反应：4，5-二羧酸咪唑40g，醋酐1200ml，回流10h，过滤并将滤液浓缩至干，所得固体加至50%的乙醇溶液回流，过滤并将滤液自然冷却过夜，过滤得固体；2 酯化反应：4(5)-羧酸咪唑50g，乙醇1000ml和浓硫酸60ml，加热回流2h，5%浓度NaOH溶液调节至pH＝8，减压浓缩至干，加入少量水回流，自然冷却过夜并过滤得固体；3 还原反应：LiAlH410g，乙醚300ml和4(5)-羧酸咪唑乙酯28g，常温反应1.5h，小心滴加25ml水后过滤，滤渣溶于300ml甲醇中并过滤，收集所得乙醚和甲醇滤液浓缩至干，将所得固体溶于300ml乙醇中加热回流，后将溶液浓缩至约30ml，冷却并过滤得固体，该路线总收率为49.6%。

The objective of the paper is to state the necessity of introducing Pinus pinaster Ait. in China. Firstly, generalize the biological and ecological characteristic of P. pinaster, and its utilization value. Secondly, after analyzing the natural distributions of P. pinaster and natural conditions of these areas, comparing the climate attributes of the introduced regions in our country and other countries, the possibility of introducing this species are discussed.

概括了沙地海岸松的生物学、生态学特性及其推广利用价值；通过了解沙地海岸松在国外自然分布区以及引种地区的自然概况，总结中国沿海防护林建设中出现的问题和亟待引进优良品种的迫切性，并对中国沿海地区的气候特点进行了对比分析得出，中国引进沙地海岸松的必要性和可行性。

For example when you pause your retrieve, the 3X Craw will stand up behind your weight and the pinchers will flare up just like a real crayfish! It won't lay on the bottom like a normal plastic craw will, which is not realistic Fig.

假如做个尝试，用一个3X 的吓饵虫做个试验，当你停止收线，做一个的停顿，软饵会轻触地面后在铅坠上立起，虾钳会向上方张开，随水流飘动，张牙舞爪，仿似一只真正的自然饵虫，而一般的普通塑料虾饵却只能平躺在水底，看上去和死的一样，一点也不自然（图片7）。

By analyzing the inherent relationship among the image plane,the mirror plane and the correspondences,this paper puts forward a novel way for 3D hand reconstruction,which not only facilitates theoretically analyses for further research,but also make it easy to reconstruct a 3D object with high accuracy.

1引言人机交互和信息处理是21世纪公认的四项重大技术之一，基于视觉的自然手的重建和识别是实现自然和谐的人机交互系统的一个关键问题，也是进一步进行基于视觉的虚拟手研究中要解决的一个瓶颈问题。

Numerical simulation results show that the typical features of primary flow, secondary flow and velocity redistribution in natural river bends are closely related to the special planform and flow depth conditions of natural river meanders. The lateral redistribution of flow is significant when water depth is small. The main stream approaches the concave bank upstream the bend vertex when river width is small.

数值试验结果表明，自然河流河弯中的主流、二次环流和流速重分布特征是与自然河弯的特殊几何形态特征、水深条件紧密相连的，水深越小则流速沿横向的重分布越为显著；河宽越小则水流动力轴线在凹岸的顶冲点越为提前。

The invention discloses a natural temperature varying intelligent calibration system of ground-based microwave radiometer, which is composed of a micro radiometer, a natural temperature varying calibration load, a platinum resistance thermometer, a thermometric instrument, a voltage collecting card and a computer.

本发明公开了一种地基微波辐射计自然变温智能定标系统，由微波辐射计、自然变温定标源、铂电阻温度计、测温仪、电压采集卡和计算机组成。

Cicero and Augustine's theory of natural theology were both based upon Platonism in one hand, in other hand reflected the limitation of natural theology through different political philosophy view.

本文分析了西塞罗和奥古斯丁关于自然神学的论述，指出他们基于柏拉图主义的共同背景所具有的一致性，也指出他们基于不同的政治哲学语境以不同的视野反思自然神学的局限性。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。