晚明商人借贷的利息率与商业性借贷的发展

商人借贷利息率的高低对商业性借贷的发展有直接的影响。晚明商人借贷的利息率总体上以低于年息36％为多,这一利率既大大低于消费性借贷的利息率,又低于市场平均利息率,一般均在法定利息率的范围之内。虽然商人借贷的利息率相对较低,但在风险机制的作用下,放贷者向商人放贷的积极性不会受到减损。又由于利率较低,商人借贷通常有利可图,因而商业性借贷能够得到发展。     

Soluble Salts Amplify the Effect of Small Heterogeneities in the Structure of Porous Building Materials During Drying

Salt crystallization is a major cause of degradation in old buildings. One of the issues that stills need clarification is regarding the influence of the salts on the capillary absorption and subsequent drying of porous building materials. This article presents an experimental study that included capillary absorption and evaporative drying tests on two types of material (lime mortar and ceramic brick) using pure water or saturated solutions of six salts (sodium chloride, sodium sulfate, sodium nitrate, sodium carbonate, potassium nitrate, or potassium carbonate). The results of capillary absorption agree only roughly with the linear relationship, predicted by theory, between sorptivity and the square root of the ratio between viscosity η and surface tension σ of the solution (σ/η)^1/2. This poor agreement is probably due to material heterogeneity. The drying dynamics was regular and showed little dispersion between specimens, but only for the uncontaminated materials. Indeed, the drying dynamics of the salt contaminated materials was often irregular or diverged among similar specimens, and the same happened with their salt decay patterns. The main conclusion is that soluble salts can amplify the effects on drying of the small structural heterogeneities that porous building materials normally depict.     

Experimental Research with Salt Crystallization in Historical Portuguese Azulejos

The most serious form of degradation of historical azulejos is the spall of the glaze and it is widely accepted that the crystallization of salts dissolved in water circulating in the masonry is its main cause. This article reports the results of an accelerated aging test aimed at studying the physical deterioration of azulejos caused by cycles of dissolution and re-crystallization of sodium chloride (NaCl). Experiments were carried out on 26 Portuguese azulejos from the 17th–19th century, some of which with original manufacturing defects or with varying degrees of previous decay.

The results of 75 cycles over 18 months did not verify that the action of NaCl could trigger an accelerated loss of glaze in a healthy azulejo. Furthermore, the results lead to the induction that there must be other, eventually concurring, causes for the spall of glaze than a simple challenge with salts that crystallize by evaporation.     

西安市市民出游行为研究

本文在详细的市场调查基础上,分析了西安市民出游的行为特征,重点探讨了行为特征形成的深层原因,并对以西安为代表的内陆大城市和沿海城市居民出游规律做了对比分析,从而对西安市民的出游行为有了较深刻的认识,为西安市旅游决策提供了科学的依据。     

Degradation of Archaeological Wood Under Freezing and Thawing Conditions—Effects of Permafrost and Climate Change

The degradation of archaeological wood at freezing and thawing temperatures is studied at the site of Qajaa in West Greenland through a combination of environmental monitoring, measurement of oxygen consumption and microscopy of wood samples. Permanently frozen wood is still very well preserved after 2–4000 years, while wood samples that thaw every summer show attack by soft rot and an average density loss of 0.1 g cm^–3 (corresponding to 25% of the dry mass) over the past 27 years. Future increases in temperature may increase the decay rate significantly (Q₁₀ = 4.2 at 0–10°C) but the effects on site depend on local hydrology.     

人民币汇率变动与中美贸易失衡的双重审视

本文针对中美贸易摩擦不断升级这一现状,提出在国际贸易中,由于各方更加关心以本国货币结算的贸易额度以及实物形式的贸易总量,因此只有在剔除了通货膨胀的条件下,以本国货币结算的贸易总额才能在一定程度上代表对外贸易的实物量的整体理论框架。并利用2006～2011年相关数据从中美两国各自视角对人民币汇率变动与中美贸易失衡的关系进行实证分析,揭示了两者动态关联性中更深层次的客观现实。研究结果表明：人民币汇率变动对中美贸易影响的程度和方向并不明确,人民币汇率不是中美贸易失衡的主要原因等结论。并提出政府应根据不同商品类别制订区别性政策,积极推进所有权统计体系的建立,加强亚洲国家间货币合作等政策建议。     

On the intrinsic accuracy and precision of luminescence dating techniques for fired ceramics

Luminescence dating techniques have been used extensively for archaeological and geological samples. Such techniques are based on thermally or optically stimulated signals. This paper presents simulations of several luminescence techniques for equivalent dose (ED) estimation for ceramic materials containing quartz. The simulations are carried out using a recently published comprehensive kinetic model for quartz, consisting of 11 electron and hole traps and centers. The complete sequence of the experimental protocols for several thermoluminescence (TL) and optically stimulated luminescence (OSL) techniques are simulated using the same set of kinetic parameters. The specific simulated protocols are: additive dose TL protocol, predose technique (both additive and multiple activation versions), phototransfer protocol, single aliquot regenerative optically stimulated luminescence (SAR-OSL) protocol, and SAR thermoluminescence protocol (SAR-TL). One hundred random variants of the natural samples were generated by keeping the transition probabilities between energy levels fixed, while allowing simultaneous random variations of the concentrations of the 11 energy levels. The relative intrinsic accuracy and precision of the protocols are simulated by calculating the equivalent dose (ED) within the model, for a given natural burial dose of the sample. The intrinsic accuracy of these techniques is estimated by simulating natural irradiation of the samples with a known burial dose, followed by simulation of the luminescence method used to recover the estimated dose ED. The percent difference between the burial dose and the ED value represents the simulated accuracy of the luminescence technique. The relative intrinsic precision of these techniques is estimated by fitting Gaussian probability functions to the ED values obtained with the 100 model variants. It is found that the various techniques can reproduce natural paleodoses in the range 10 mGy–10 Gy with a typical intrinsic accuracy of +1 to 10%. Techniques based on single aliquot protocols were found in general to be more precise than techniques requiring the use of multiple aliquots. In addition, techniques based on interpolation of experimental data were found to be consistently both more precise and accurate than those based on extrapolation of experimental data.     

New trials in the consolidation of waterlogged archaeological wood with different acetone-carried products

Some acetone-carried consolidants for waterlogged archaeological wood were tested in order to evaluate treatments able to save time and energy. In details, colophony (rosin), two esterified colophonies (Rosin 100^® and Rosin 459^®), a mixture of colophony with PEG 3400 and a vinyl acetate - vinyl versate copolymer (Vinavil 8020S^®) were tested. The treatments were carried out at temperatures of 20 and 35 °C on waterlogged maritime pine, elm, oak and beech. The materials came from the archaeological site of the ancient ships of Pisa (Tuscany, Italy) and were dated back to VII cent. BC – II cent. AD. To evaluate the processes, equilibrium moisture content and dimensional stability of treated wood samples at different relative humidity, and retention of impregnating products were measured; moreover macroscopic and microscopic examination were also run to respectively assess the shape and appearance of treated wood and the way of deposition of consolidants. The results highlighted that natural and modified colophony treatments gave the most satisfactory results both in the maintenance of shape and dimensions of samples and in the stabilization with respect to RH variations. Moreover, the equilibrium moisture contents of samples treated with R100 and R459 were much reduced in comparison to the other consolidants and to untreated archaeological wood. This fact was related to the high retention values of those products that occluded most of the porosity including the microporosity of cell walls. Therefore, in terms of higroscopicity treated wood was more similar to impregnating substances rather than to decayed wood. This fact was considered helpful in contrasting the moisture-related negative effects in cases of eventual faults in the climate control during e.g. exhibition and in protecting treated wood from the risks of new fungal attacks.     

华茶销售衰败与祁红统制运销中的官商权势纷争

民国年间,华茶的生产和销售与国际市场联系尤为紧密,其产销受到国民政府和商界的高度重视。由于受到国际茶叶市场供需关系的制约,华茶特别是红茶销售日益衰败。为振兴华茶,皖赣两省实施红茶统制运销政策,祁门红茶是统制运销的主要对象。官商之间为祁红统制运销的控制权展开博弈。华茶销售的衰败和祁红统制运销中的权势纷争凸显出民国现代化转型时期商业社会生态的变迁面相,在一定程度上折射出民国时期商业发展的步履艰难。