Effects of Periodic Temperature Changes on Stress Relaxation of Chemically Treated Wood

In order to clarify the relationship between the microstructural changes and the rheological behaviors of four chemically treated woods (delignified wood, hemicellulose-removed wood, DMSO swollen and decrystallization treated wood), the stress relaxation of wood with three different moisture contents was determined during periodic temperature changes. The experi- mental results show that after wood relaxation for 4 h at 25 °C, the stress decays sharply when the temperature increases and 2 h later the stress recovers again when the temperature drops back to the original point. The additional stress relaxation, produced after tem- perature begins to increase, is mainly caused by the thermal swelling, molecular thermal movement and the break of a part of residual hydrogen bonds. The number of hydrogen bonds and the size and amount of cavities in various treated woods greatly affect the magnitude of the additional relaxed stress and the recovery stress.

Wavelet analysis of quasi-3-year temperature oscillations in China in last 50 years, and predicted changes in the next 20 years

The wavelet analysis method is used to analyze the annual and winter temperature data of 98 observation stations in China in eight climate zones during the last 50 years （1961-2009）. The periodicities of temperature changes are investigated, and the possible temperature change trends in China in the next 20 years （2012-2029） are also predicted. Our results show that in the inter-annual temperature variability there are pervasive quasi-3- to quasi-4-year cycles, and these cycle changes are relatively steady. The periodic characteristics of the annual temperature changes are clearly different between northern and southern China, and our period superimposition extrapolation shows that both annual and winter temperatures in China will continue to increase in the next 20 years, more so in northern China and in the Qinghai-Xizang Plateau （QXP） than in the southern region, except in the southwest. If temperatures follow historic increasing linear trends, the overall temper- ature is expected to increase by 1℃ between 2010 and 2029.

Characteristics of Temperature Change in China over the Last 2000 years and Spatial Patterns of Dryness/Wetness during Cold and Warm Periods

This paper presents new high-resolution proxies and paleoclimatic reconstructions for studying climate changes in China for the past 2000 years. Multi-proxy synthesized reconstructions show that temperature variation in China has exhibited significant 50–70-yr, 100–120-yr, and 200–250-yr cycles. Results also show that the amplitudes of decadal and centennial temperature variation were 1.3℃ and 0.7℃, respectively, with the latter significantly correlated with long-term changes in solar radiation, especially cold periods, which correspond approximately to sunspot minima. The most rapid warming in China occurred over AD 1870–2000, at a rate of 0.56°± 0.42℃（100 yr）^（-1）; however, temperatures recorded in the 20 th century may not be unprecedented for the last 2000 years, as data show records for the periods AD 981–1100 and AD1201–70 are comparable to the present. The ensemble means of dryness/wetness spatial patterns in eastern China across all centennial warm periods illustrate a tripole pattern： dry south of 25°N, wet from 25°–30°N, and dry to the north of 30°N. However, for all centennial cold periods, this spatial pattern also exhibits a meridional distribution. The increase in precipitation over the monsoonal regions of China associated with the 20 th century warming can primarily be attributed to a mega El Nino–Southern Oscillation and the Atlantic Multidecadal Oscillation. In addition, a significant association between increasing numbers of locusts and dry/cold conditions is found in eastern China. Plague intensity also generally increases in concert with wetness in northern China, while more precipitation is likely to have a negative effect in southern China.

Spatial / Temporal Features of Antarctic Climate Change

Bused on January 1962-October 1993 mean value series of monthly mean temperature anomalies of 16 Antarctic stations on 10 standard isobanc surfaces from the surface to the 30 hPa,long term trends and periodic features of climate changes from the troposphere to the lower stratosphere over the Antarctic region are investigated by maximum entropy power spectrum analysis,and the relation between climate change of the stratosphere (troposphere) and tolal ozone (southern 500 hPa circulation) is discussed.

Changes of the Period and the Light Curves of the Contact Binary V1073 Cygni

Observational evidence of unstable behavior for the W UMa type binary system V1073 Cygni is presented in this paper. Around 1939 the period of the binary suddenly decreased by 0 580 seconds and again suddenly decreased by 0 746 seconds around 1981.Obvious variable O’ Connell effect of the light curves in V can be seen. The relation between the changes in the orbital period and variation in the O’ Connell effect and possible reasons for the unstable behavior of V1073 Cyg were discussed.

Periodic Analysis on Nutrients in Chinese Residents and Their Sources

The nutritional status of Chinese residents has been greatly improved during the past 50 years.Compared with Japanese people to whom our food consumption habit is similar,the calorie nutrient intake and fat nutrient intake per capita of Chinese residents has exceeded the intake of the Japanese residents,but the protein nutrient intake is still lower.Among the composition of the calorie nutrient,the proportion of fat is higher,but the proportion of protein is lower,and both the animal protein and the vegetable fat are small.Therefore,we should guide the poor to the rational consumption such as soybean which contains quality protein but is a kind of inexpensive food.With the increase of population eating out,residents＇ nutrients awareness as well as the public service institutions knowledge of nutrition should be enhanced.

A research on the relationship between ejaculation and serum testosterone level in men

The purpose of this study is to gain understanding of the relationshi p between ejaculation and serum testosterone level in men. The serum testosteron e concentrations of 28 volunteers were investigated daily during abstinence peri ods after ejaculation for two phases. The authors found that the fluctuations o f testosterone levels from the 2nd to 5th day of abstinence were minimal. On the 7th day of abstinence, however, a clear peak of serum testosterone appeared, re aching 145.7% of the baseline (P<0.01). No regular fluctuation was observed foll owing continuous abstinence after the peak. Ejaculation is the precondition and beginning of the special periodic serum testosterone level variations, which wou ld not occur without ejaculation. The results showed that ejaculation-caused va r iations were characterized by a peak on the 7th day of abstinence; and that the effective time of an ejaculation is 7 days minimum. These data are the first to document the phenomenon of the periodic change in serum testosterone level; the correlation between ejaculation and periodic change in the serum testosterone le vel, and the pattern and characteristics of the periodic change.

Study on microbial protein and the mechanism of solid-state fermentation with periodical dynamic changes of air

The effect of different extraction and purification conditions on the microbial protein obtained from solid-state fermentation(SSF)and the effect of periodical dynamic changes of air on protein have been studied.The mechanism of solid-state fermentation with periodical dynamic changes of air is also discussed.Compared with static solid-state fermentation,periodical dynamic changes of air afford a higher protein mass;from 1 g of the fermentation microbe,5.3 mg of the intracellular protein(an increase of 34.63%)and 9.09 mg of the extracellular protein(an increase of 17.8%)were obtained on the sixth day of fermentation.The filter paper activity and carboxymethyl cellulose activity(FPA and CMCase)of the extracellular protein are 1.739μmol/s and 109.592μmol/s,respectively,which represent increases of 60.1%and 21.2%over the corresponding values for static solid-state fermentation.The FPA and CMCase of the intra-cellular protein are 0.245μmol/s and 6.392μmol/s,respec-tively,which represent decreases of 22.2%and 38.7%over the corresponding values for static solid-state fermentation.The enzyme activity of the microbial extracellular protein in solid-state fermentation with periodical dynamic changes of air on the fifth day is nearly equal to that on the sixth day without periodical dynamic changes of air,so the period of fermentation can be shortened.The sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE)experiments suggest that pulsating air pressure stimulation leads to a decrease in the amount of protein component with molecule mass of about 80400Da,and an increase in the amount of protein component with molecule mass of about 28520Da.

On the Period Variation of the W UMa-type Contact Binary V502 Ophiuchi

The variation in the orbital period of the W UMa type contact binary V502 Oph is analyzed. The orbital period exhibits a wavelike variation with a periodicity of 23.0 years and an amplitude of AP = 1.24 ×10^-5 days superimposed on secular decrease of dP/dt = 1.68× 10^-7 day per year. The long-term decrease may be accompanied by the contraction of the secondary at a rate of 83 m per year and a mass transfer rate from the primary to the secondary of 4.28×10^-8M· per year. The short-term oscillation may be explained by the presence of a third component. Orbital elements of the third body and its possible mass are presented.

Decadal change of East Asian summer tropospheric temperature meridional gradient around the early 1990s

During 1979–2004, the East Asian summer precipitation has experienced another significant decadal shift around the early 1990 s. Based on three radiosonde temperature datasets and four reanalysis datasets, this paper examines the decadal change of the East Asian summer tropospheric temperature around the early 1990 s. The results show that the meridional gradient of layer mean upper tropospheric temperature for 200–500 h Pa(here after UTT, UTT is upper tropospheric temperature) also underwent an obvious decadal decrease around 1992. The tropospheric temperature south to 35°N becomes decadal cooling, centered along the Yangtze River Valley, while the tropospheric temperature north to 35°N shows a decadal warming, centered in Northwest China-Mongolia. JRA-25 reanalysis is better than the other reanalysis datasets in revealing this decadal change. This decadal shift of East Asian summer UTT may be ascribed to the decadal change of the ENSO period from low-frequency oscillation(4–6 yr) to quasi-biennial oscillation since 1992. It behaves as an increase of ENSO developing events and a reduction of ENSO decaying events. It leads to stronger forcing of ENSO developing summer and weaker forcing of ENSO decaying summer, leading to the dominant role of monopole cooling mode of East Asian UTT after 1992, in contrast to the dominant role of dipole mode of East Asia UTT before 1992. The summer UTT difference between 1993–2004 and 1979–1992 shows a "South cooling-North Warming" pattern, and thereby contributes to the interdecadal decrease of East Asian summer UTT meridional gradient around 1992.

Restoration of eroded stratal thickness in key periods of tectonic change in a multi-stage superimposed Tarim Basin in China

With an area of 56×104km2, the Tarim Basin is the largest inland basin in China and is also generally acknowledged as one of the most important areas for potential oil and gas exploration. On the basis of data from 22 regional seismic profiles and 40 drilling wells, 15 important first-order and second-order regional unconformities were defined.Almost all the main unconformities are superimposed unconfomities. Since the Cambrian, 5 key periods of tectonic change have occurred during the evolution of the Tarim Basin. The total eroded stratal thickness of the above-mentioned unconformities was calculated by using the method of virtual extrapolation of seismic reflection. The results indicate that the total eroded stratal thickness of different periods is quite different in different locations of the basin. Taking the Upper-Middle Ordovician as an example, its thickness restoration of eroded strata was calculated into individual stages i.e. its thickness restoration of eroded strata was calculated to different tectonic periods. Otherwise, as for the specific period of tectonic change, the underlying strata were, respectively eroded and thus the thickness restoration of eroded strata was calculated into individual intervals. Taking the Early Hercynian period as an example, the eroded stratal thickness was calculated into individual intervals to calculate the ratio of intervals of various ages occupying the total eroded thickness. The results show that for the same stratum, its degree of erosion is quite different in different periods and at different locations, due to the varying influence of tectonic movement. The unconformities of some key periods of tectonic change have different controls on the degree of erosion and the eroded range of the individual period of the underlying strata which are the typical characteristics of multi-stage superimposition of unconformities in the Tarim Basin.

Changes of the Important Period of Strategic Opportunities and Our Response

Currently,the fundamental judgment that China remains in an important period of strategic opportunities for its development has not changed,however new changes have taken place in the nature and the conditions of this period.On a higher starting point of development,China is faced with unprecedented opportunities for development as well as challenges unknown before.