Improved computation of pressure coefficient and temperature coefficient of ultrasonic velocity in organic liquids

Based on Jacobson’s molecular free length theory in liquids and the relationship between the ultrasonic velocity and the molecular free length in organic liquids, the equations of pressure coefficient and temperature coefficient of ultrasonic velocity in organic liquids are derived. The calculated pressure coefficient and temperature coefficient of ultrasonic velocity are in good agreement with the measured results.     

基于Schaaffs理论的有机液声速压力系数和温度系数

基于Schaaffs理论，从有机液声速与液体分子碰撞因子关系式出发，导出了反映有机液声速压力和温度特性的声速压力系数和温度系数表达式，并与由Jacobson分子自由程-声速理论导出的表达式进行了比较，比较结果表明，两级公式计算出的几种有机液的声速压力系数和温度系数相互吻合，且均与实验值吻合较好，从理论上讲，本文中推导出的有机液声速压力系数和温度系数公式更具合理性。     

Relationship between echolocation frequency and body size in two species of hipposiderid bats

Frequencies of echolocation calls with maximum power of Himalayan leaf-nosed bats and Horsfield’s leaf-nosed bats during searching phase were 74.1 and 92.1 kHz, respectively. Head-body length, forearm length and body mass of Himalayan leaf-nosed bats were 82.9 mm, 89.7 mm and 59.1 g, respectively; and the corresponding values of Horsfield’s leaf-nosed bats were 68.4 mm, 61.3 mm and 19.7 g, respectively. Echolocation frequency and the three parameters of body size, head-body length, forearm length and body mass, were all negatively correlated, and the correlation coefficients were −0.86, −1.58 and −2.19, respectively. This study thereby proved that echolocation frequency and body size were negatively correlated in the two species of hipposiderid bats.     

Synthetic seismograms of ground motion near earthquake fault using simulated Green’s function method

Seismograms near source fault were synthesized using the hybrid empirical Green＇s function method where the discretely simulated seismic waveforms are used for Green＇s functions instead of the observed waveforms of small earthquakes. The Green＇s function seismic waveforms for small earthquake were calculated by solving wave equation using the pseudo-spectral method with the staggered grid real FFT strategy under a detailed 2-D velocity structure in Kobe region. Magnitude and seismic moment of simulated Green＇s function waveforms were firstly determined by using the relationship between fault length and corner frequency of source spectrum. The simulated Green＇s function waveforms were employed to synthesize seismograms of strong ground motion near the earthquake fault. The synthetic seismograms of the target earthquake were performed based on the model with multiple source rupture processes. The results suggest that synthesized seismograms coincide well with observed seismic waveforms of the 1995 Hyogo-ken Nanbu earthquake. The simulated Green＇s function method is very useful for prediction of the strong ground motion in region without observed seismic waveforms. The present technique spreads application field of the empirical Green＇s function method.     

液体声速压力系数与分子有效摩尔体积关系研究

由液体声速与自由程关系出发,导出声速压力系数表达式,并结合Ｋｕｃｚｅｒａ的结论,研究了液体分子有效摩尔体积与分子势能的关系．     

多元有机混合液体非线性声参量的混合定则

给出了多元有机混合液体的非线性声参量所满足的混合定则 ,在组成混合液体非线性声参量、摩尔分数、内表面积、自由程参量已知的情况下 ,可以计算出混合液体的非线性声参量。实验测量结果与混合定则给出的理论值符合较好     

A tubular focused sonochemistry reactor

This paper presents a new sonochemistry reactor, which consists of a cylindrical tube with a certain length and piezoelectric transducers at tube’s end with the longitudinal vibration. The tube can effectively transform the longitudinal vibration into the radial vibration and thereby generates ultrasound. Furthermore, ultrasound can be focused to form high-intensity ultrasonic field inside tube. The reactor boasts of simple structure and its whole vessel wall can radiate ultrasound so that the electroacoustic transfer efficiency is high. The focused ultrasonic field provides good condition for sonochemical reaction. The length of the reactor can be up to 2 meters, and liquids can pass through it continuously, so it can be widely applied in liquid processing such as sonochemistry.     

Attracted by the same sex, or repelled by the opposite sex?

Sexual segregation behavior has attracted deep interest of zoologists in recent years. People have put forward many hypotheses to explain the phenomenon. We recommended two indices for measuring the intensity of aggregation and sexual segregation in animals, and applied those measurements to the study of aggregation and sexual segregation in free-ranging Pere David’s deer. We quantified the aggregation and segregation behavior with those methods and compared the intensities of sexual segregation in different seasons with statistic means. At the same time, the Nutritional Strategy Hypothesis, the Social-factor Hypothesis and Reproductive Strategy Hypothesis were tested in the study. We discovered that aggregation in free ranging Pere David’s deer was high in winter but low in summer. Sexual segregation in free ranging Pere Danid’s deer is caused by the reproductive strategy of different sexes, the highest degree of sexual segregation was found in the breeding season not the non-breeding season in the free ranging Pere David’s deer.     

Hardness estimation for covalent crystals using empirical electron theory

Covalent electrons substantially determine the intrinsic hardness of inorganic crystals. A hardness model is presented on the basis of the Empirical Electron Theory generated from Pauling’s covalent bond length equation and the bond length difference method. The calculated hardness values of inorganic crystals are in good agreement with experimental and other theoretical values. Covalent bond energy with polarity correction can be used as an intrinsic indicator linking microscopic electronic structure to macroscopic hardness. A simple mathematical processing of bond energy is performed to extend the model to multi-bonding or multi-component systems. It is also found that spatial distribution of covalent bonds has a great influence on the hardness of inorganic crystals.     

Salt glands inGlycine soja L. China

A scanning electron microscope observation is carried out on Glycine soja L., which grows around the estuary of the Yellow River, in Kenli County, Shandong Province. It is first discovered that there are salt glands, in the shape of balls, on the surface of the stems and leaves of G. soja L., and distributed at the intercellular layer. With a handle at the base, the salt glands are not equal in size, and show a layer-upon-layer structure. They have a diameter of 21.6 μm, a handle length of 1.2 μm, their secretory pore's diameter is 5.6 μm. There are two ways to secrete salt ions: younger glands secrete salt ions through the secretory pore, and mature glands by breaking themselves.     

Experimental validation of inter-subspecific genetic diversity in rice represented by the differences between the DNA sequences of ＇Nipponbare＇ and ＇93-11＇

The pedigrees of three sequenced rice cultivars were analyzed to show that a majority of the genetic composition of ＇Nipponbare＇ originates from japonica cultivars while the minority originates from indica cultivars. In contrast, ＇93-11＇ is derived mainly from indica cultivars with a smaller contribution from japonica cultivars. All ancestors of ＇Guang lu ai 4＇ appeared to be indica lines. A set of molecular markers （46 InDels and 53 SSRs） polymorphic between ＇Nipponbare＇ and ＇93-11＇ were examined in 46 typical indica and 47 typical japonica cultivars selected from 443 accessions according to Cheng＇s index. All cultivars were divided into indica and japonica groups without overlapping when clustered by Cheng＇s index, InDels and SSRs. Much higher InDel and SSR diversity between groups than within groups implies that the marker polymorphisms between ＇Nipponbare＇ and ＇93-11＇ represent a large proportion of inter-subspecific diversity. About 85% of indica cultivars and more than 90% of japonica cultivars were confirmed to have the same PCR banding patterns as ＇93-11＇ and ＇Nipponbare＇, respectively. Some polymorphic loci between ＇Nipponbare＇ and ＇93-11＇ cannot be validated in other indica and japonica cultivars, either as subspecies-specific but not predominant alleles, or alleles not specific between the two groups. It was concluded that molecular markers developed from sequence polymorphism between ＇Nipponbare＇ and ＇93-11＇ often represent inter-subspecific diversity, although some exceptions were sensitive to either particular marker loci or particular cultivars.     

Simulation investigations in the binding energy and mechanical properties of HMX-based polymer-bonded explosives

The molecular simulations of the well-known high explosive [β-HMX (cyclotetramethylene tetranitramine) and its fluorine containing polymer-bonded explosives (PBXs) were carried out with the combination method of quantum mechanics, molecular mechanics and molecular dynamics. The atomic cluster model, containing the [β-HMX molecule and the polymer molecule whose chain dimension was about the same as β-HMX‘s, was fully optimized by AM1 and PM3 semi-empirical molecular orbital and molecular mechanical methods using COMPASS and PCFF force field. Then the calculated binding energy is found to be linearly correlated to each other. Molecular dynamics simulations using COMPASS force field were performed for [~-HMX crystal and the PBXs involving [β-HMX and a series of fluorine containing polymers. Their elastic coefficients, moduli and Poisson‘s ratios were calculated. It is found that the mechanical properties of β-HMX can be effectively improved by blending with fluorine containing polymers in small amounts.     

Enthalpy-entropy compensation in protein unfolding

Enthalpy-entropy compensation was found to be a universal law in protein unfolding based on over 3000 experimental data. Water molecular reorganization accompanying the protein unfolding was suggested as the origin of the enthalpy-entropy compensation in protein unfolding. It is indicated that the enthalpy-entropy compensation constitutes the physical foundation that satisfies the biological need of the small free energy changes in protein unfolding, without the sacrifice of the bio-diversity of proteins. The enthalpy-entropy compensation theory proposed herein also provides valuable insights into the Privalov’s puzzle of enthalpy and entropy convergence in protein unfolding.     

Evaluation and characterization of an endosperm-specific sbeⅡa promoter in wheat

Starch,the main component of the wheat grain,is the product of a complex biochemical pathway. The sbeⅡα gene plays a key role in controlling the synthesis of starch, in particular, the biosynthesis of amylopectin,in maturing wheat grain.To investigate its regulatory mechanisms and endosperm-specific expression pattern, the sbeⅡα promoter (3094 bp in length) was cloned using APCR and sequenced.The effect of a series of deletions was studied using a GUS transient assay system. Results showed that the 3094 bp sequence (sbe.g construct) exhibited full stable promoting activity and that the activities of 5′ or 3′ deletions reduced levels of GUS expression. Some constructs with internal deletions showed only weak activity, however,sbe.e, with a deletion from -1579—--1210 bp resulted in higher levels of expression than the full-length promoter sequence, sbe.g. This indicates that motifs such as the -300 bp element, G-box and/or P-box act as positive elements and are necessary in determining the promoter‘s endosperm-specific pattern and that negative repressor elements or motifs may also be present within the -1579—-1210 bp sequence. The age of wheate ndosperm tissue used in the GUS-transient assay system is shown to be of significant importance.     

Modulation of low-frequency oscillations in GaAs MESFETs’ channel current by sidegating bias

Low-frequency oscillations in channel current are usually observed when measuring the GaAs MESFET‘s output characteristics. This paper studies the oscillations by testing the MESFET‘s output characteristics under different sidegate bias conditions. It is shown that the low-frequency oscillations of channel current are directly related to the sidegate bias. In other words, the sidegate bias can modulate the oscillations. Whether the sidegate bias varies positively or negatively, there will inevitably be a threshold voltage after which the low-frequency oscillations disappear. The observation is strongly dependent upon the peculiarities of channel-substrate (C-S) junction and impact ionization of traps-EL2 under high field. This conclusion is of particular pertinence to the design of low-noise GaAs IC‘s.     

Research of Inclusion Complexation of 4,4＇-Thiodiphenol Effected by β-Cyclodextrin in Aqueous Solutions and the Effect on Photodegradation

The inclusion behavior of 4, 4＇ -Thiodiphenol （TDP）, a typical bisphenol and endocrine disruptor, reacts with β-cyclodextrin （β-CD） in aqueous solutions has been investigated by means of UV absorption spectrum and quantum-chemical calculation with Gaussian 98 software. The results show that the inclusion behavior of TDP is quite different in acidic solutions （pH 5.9） from that in alkaline solutions （pH 10.0）. This behavior difference is attributed to the different formula structures in aqueous solutions at acidic and alkaline pH values that are demonstrated by quantum- chemical modeling and calculation. TDP forms a 1 ： 1 fl-CD inclusion complex in aqueous solutions. The equiiibrium constant K was calculated to be 553.49 L/mol at pH 5.9 and 1 318.20 L/mol at pH 10.0 respectively for the inclusion complex reaction by using the modified Benesi-Heldbrand equation. After inclusion TDP＇s structure is changed especially at the inclusion part with the bond order becoming larger, which results in inhibitive photodegradation during direct photooxidation and H2O2 assisted photooxidation.     

Divisional and hierarchical innervations of G. gecko’s toes to motion and reception

As a member of robot families, climbing robots have become one of the research hot-spots in the robotic field recently and Gekko gecko （G. gecko） has been broadly seen as an ideal model for climbing robot development. But for gecko-mimic robots, one of the key problems is how to design the robot＇s foot. In this paper, （1） high-speed camera recording and electrophysiological method are used to observe motion patterns of G. gecko＇s foot when it climbs on different oriented surfaces; （2） nerve innervations of gecko＇s toes to motion and reception are studied. It is found that the five toes of the G. gecko can be divided into two motion and reception divisions, and also its motion and reception are modulated and controlled hierarchically. The results provide important information and exclusive ideas for the foot design and control algorithm of gecko-mimic robots.     

Development in the research of molecular mechanism of Alzheimer’s disease

Alzheimer's disease (AD) is a kind of central nervous system disease. The cause of AD is unclear. It is found that the remarkable histopathological characters of AD are senile plaques and neurofibrillary tangles. β-amyloid plays an important role in the formation of senile plaques and the abnormal phosphorylation of Tau protein is the main reason of neurofibrillary tangles. Apolipoprotein E is correlated to AD' s access, and the third pathological character-AMY plaque perhaps represents a new cause of AD. Presenlin and proteinaceous infectious particles are also related with AD. A summary of molecular mechanism for AD and the development of research is presented.     

Strong Law of Large Numbers and Complete Convergence for Sequences of φ-Mixing Random Var, ables

We give some theorems of strong law of large numbers and complete convergence for sequences of φ-mixing random variables. In particular, Wittmann＇s strong law of large numbers and Teicher＇s strong law of large nnumbers for independent random variables are generalized to the case of φ -minxing random variables.     

QTL analysis of the rice seedling cold tolerance in a double haploid population derived from anther culture of a hybrid betweenindica andjaponica rice

A doubled haploid population, derived from anther culture of F₁ hybrid between a typicalindica cv. and ajaponica cv. has been used to investigate the seedling cold tolerance (SCT) in growth cabinet. By dynamically analyzing every day’s survival percentages of the parents and DH lines under 7-d cold plus 9-d normal temperature condition, the quantitative trait loci (QTLs) for SCT have been mapped based on a molecular linkage map constructed from this population. The results show that two parents had significant differences in SCT and the segregation of SCT in DH lines was basically a continuous distribution with most serious injury on the 6th d of the cold treatment. A total of 4 QTLs for SCT have been identified on chromosomes 1, 2, 3 and 4 respectively. The additive effects of qSCT-1, qSCT-2 and qSCT-3 have been contributed by thejaponica cv JX17, but that of qSCT-4 has been contributed by theindica cv ZYQ8. The mechanism of SCT seems complicated since the above 4 QTLs detected at different stages during the treatment. Further study on the genotypes for these SCT QTLs in the DH lines shows transgressive segregation. It is demonstrated that the lines with stronger SCT over JXI7 have 3–4 loci for SCT. Integration of these QTLs into an appropriate variety may lead to a successful rice breeding program for cold tolerance.