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The nuclear magnetic resonance (NMR) technique was used to study freeze–thaw damage degradation of sandstone with initial damage. The initial damage was fabricated by preloading, and the pore structure was detected using the NMR technique. Porosity, T2 spectrum distribution, and T2 spectral area were obtained. The magnetic resonance imaging (MRI) technique was used to obtain two-dimensional pore distribution images. Combined with uniaxial compressive strength tests, the effects of initial damage and freeze–thaw cycles on the mechanical properties of rock were studied and the failure mode of rock was analyzed. The results show that in the first 20 cycles, the numbers of micropores (d ≤ 1 μm) and mesopores (1 μm < d ≤ 10 μm) both increased. As the number of cycles further increased, the porosity of the sample was mainly affected by micropores. When the initial damage level is 50% or lower, as the number of freeze–thaw cycles increases, the ability of sandstone to accommodate permanent strain before failure gradually weakens and then increases again after 40 cycles. When the initial damage level reaches 70% or higher, the ability to accommodate permanent strain continues to weaken. The strain produced by sandstone before elastic deformation is roughly positively correlated with the number of mesopores and macropores in the sandstone. Under loading, the sandstone presents four failure modes: splitting failure, single shear failure, cone failure, and multi-crack failure.

To evaluate the safety of stent malapposition of corrodible nitride iron stent as biodegradable cardiovascular implants, a total of 108 stents were implanted into the abdominal aortas, iliac arteries, and iliac artery bifurcations of 36 New Zealand white rabbits separately. Each rabbit was implanted with three stents. After a follow-up period of 3 months, no thrombus and embolism were found in local and downstream vessels. And no other adverse events occurred either. Stent strut covered by endothelial layer started to show signs of degradation, while struts exposed to bifurcated blood flow covered by a layer of tissue and no rust particle was found on the surface. Also, there were no traces of thrombosis and traces of excess inflammation. The authors conclude that the risk brought by stent malapposition in less than 9 months is acceptable.

The dynamic mechanical behaviors of 7B52 laminated aluminum alloy under different impact deformation conditions were investigated using split Hopkinson pressure bar, optical microscopy, electron backscatter diffraction and transmission electron microscopy. The results show that the 7B52 laminated aluminum alloy displays positive strain rate sensitivity and negative temperature sensitivity. Cracks are formed firstly at the interface between the 7A62 hard layer and the 7A01 middle layer under a low strain rate of 2200 s−1. When the strain rate increases to 3500 s−1, the deformation shear band is firstly formed in the 7A52 soft layer. The deformation shear band transformed to the transition shear band with the increase of strain rate, and then crack initiated. Adiabatic shear bands and cracks are formed in both of the hard and soft layers when samples impacted at a high strain rate (5500 s−1). Most of the cracks and adiabatic shear bands are unable to penetrate the middle layer due to the good toughness of the 7A01 alloy. The deformation of each layer of 7B52 laminated aluminum alloy becomes more uniform when the temperature increases, which was attributed to the reduction of difference in strength among the three layers and the coordinating effect of grain boundary on deformation.

Additional file 1: Supplementary Material Table 1. RNA-seq Mapping Statistics.

We report the design and synthesis of cesium-doped hydroxyapatite for direct and high-yield conversion of biobased lactic acid to 2,3-pentanedione (72.3 %). Cs species derived from CsNO3 at high temperature of calcination is introduced into the hydroxyapatite structure to regulate its acid–base properties. It is found that a balance of acid–base chemistry favors the condensation of lactic acid to 2,3-pentanedione. As a result, the undesired reactions such as lactic acid dehydration, decarbonylation, and coking are suppressed. Instead, a concerted catalysis between surface basic site and acidic site for lactic acid condensation to 2,3-pentanedione dominates on the cesium-doped hydroxyapatite catalyst, leading to a highly selective process for direct conversion of bio-lactic acid to 2,3-pentanedione.

Sustainable production of 2,3-pentanedione from lactic acid over Ba2P2O7 doped with Cs was investigated. Varying Cs components and calcination temperature can efficiently tune the acid–base properties of catalysts. It was found that both base site density and acid site density had a marked impact on catalytic performance for condensation of lactic acid to 2,3-pentanedione. Enhanced base site density and acid site density favor the catalytic activity. Furthermore, base/acid molar ratio has also played an important role on catalytic performance. From the observations based on the effect of Cs doped amount and calcination temperature, an appropriate base/acid molar ratio is around 8. Low reaction temperature as well as low LA LHSV favors selective formation of 2,3-pentanedione from lactic acid over the catalyst of 1.0CsNO3/2.5Ba2P2O7 calcined at 600 °C. Encouragingly, the condensation reaction of lactic acid proceeds efficiently at around 28 h on stream, and 2,3-pentanedione selectivity remains around 60%.

The electronic structures and the magnetic properties of Fe doped GaSb have been investigated by the first-principles calculation based on the framework of the generalized gradient approximation (GGA) and GGA+ U schemes. The calculated results indicated that Fe atoms tend to form the anti-ferromagnetic (AFM) coupling with the nearest-neighbor positions preferentially. Compared with the anti-ferromagnetic coupling, the ferromagnetic interactions occurred at the second nearest-neighbor and third nearest-neighbor sites have a bigger superiority energetically. The effect of strong electron correlation at Fe- d orbit taking on the magnetic properties predicted by GGA+ U approach demonstrated that the ferromagnetic (FM) coupling between the Fe ions is even stronger in consideration of the strong electron correlation effect. The ferromagnetism in Fe doped GaSb system predicted by our investigation implied that the doping of Fe into GaSb can be as a vital routine for manufacturing the FM semiconductors with higher Curie temperature.

The dehydration of lactic acid (LA) to acrylic acid over ammonia promoted barium sulfate was studied under various conditions. Interplanar spacing (d) calculated from the enlarged (121) diffraction peak of XRD patterns with the Bragg equation is influenced by preparation conditions, which determines the acid–base properties of the prepared barium sulfate. The present work focused on the preparation conditions such as alkaline agents, pH values and calcination temperatures, which affected the d value. It was found that aqueous ammonia was used as an alkaline agent at pH = 5 to synthesize barium sulfate with an appropriate d value, which displayed an excellent catalytic performance for LA dehydration to acrylic acid. In the presence of the prepared barium sulfate with an appropriate d value, the dehydration reaction of lactic acid proceeded efficiently, with 100% lactic acid conversion and ∼82% acrylic acid selectivity. The unprecedented catalytic performance is due to a balance between acidic sites and basic sites existing on the surface of the prepared catalyst. The catalyst is very stable for at least 24 h. The deactivation catalyst can be easily regenerated as it is calcined at 500 °C for 10 h under the air atmosphere.

Differential and angle-integrated cross sections for the $^{10}$B($n, ��$)$^{7}$Li, $^{10}$B($n, ��$$_{0}$)$^{7}$Li and $^{10}$B($n, ��$$_{1}$)$^{7}$Li$^{*}$ reactions have been measured at CSNS Back-n white neutron source. Two enriched (90%) $^{10}$B samples 5.0 cm in diameter and ~85.0 $��$g/cm$^{2}$ in thickness each with an aluminum backing were prepared, and back-to-back mounted at the sample holder. The charged particles were detected using the silicon-detector array of the Light-charged Particle Detector Array (LPDA) system. The neutron energy E$_{n}$ was determined by TOF (time-of-flight) method, and the valid $��$ events were extracted from the E$_{n}$-Amplitude two-dimensional spectrum. With 15 silicon detectors, the differential cross sections of $��$-particles were measured from 19.2�� to 160.8��. Fitted with the Legendre polynomial series, the ($n, ��$) cross sections were obtained through integration. The absolute cross sections were normalized using the standard cross sections of the $^{10}$B($n, ��$)$^{7}$Li reaction in the 0.3 - 0.5 MeV neutron energy region. The measurement neutron energy range for the $^{10}$B($n, ��$)$^{7}$Li reaction is 1.0 eV $\le$ En < 2.5 MeV (67 energy points), and for the $^{10}$B($n, ��$$_{0}$)$^{7}$Li and $^{10}$B($n, ��$$_{1}$)$^{7}$Li$^{*}$ reactions is 1.0 eV $\le$ En < 1.0 MeV (59 energy points). The present results have been analyzed by the resonance reaction mechanism and the level structure of the $^{11}$B compound system, and compared with existing measurements and evaluations., 19 pages, 34 figures, to be published in Chinese Physics C

The data of neutron capture cross section are very important for the research of nuclear astrophysics, advanced nuclear energy development. Owing to the limitation of neutron source and detector, the experimental data of neutron capture cross section in an energy range of 1 eV–10 keV were almost blank in China. The first Chinese gamma-ray total absorption facility has been constructed in the key laboratory of nuclear data at China institute of atomic energy, which consists of 40 BaF2 detector units. The BaF2 crystal shell with a thickness of 15 cm and an inner radius of 10 cm covers 95.2% of the solid angle. On-line measurement method of neutron capture reaction cross section is established on the back-streaming white neutron source of China spallation neutron source by using the upgraded facility. The cross section of 197Au neutron capture reaction is measured for the first time under the experimental condition of irregular 30 mm neutron beam spot. The measured position of resonance peak is well consistent with the relevant data of ENDF evaluation database, which verifies the reliability of the measurement device and measurement technology, and thus laying the foundation for the acquisition of high precision cross section in future.

Intravascular optical coherence tomography (IVOCT) has been widely used in clinical coronary artery intervention field. Owing to defocus and contrast agent absorption effects, the intensity fluctuation caused by imaging catheter locating at an eccentric position significantly influence the quality of IVOCT imaging and even plaque type identification. In this paper, we present a novel method to compensate intensity fluctuation caused by defocus and contrast agent absorption in IVOCT imaging. We construct a principle model of IVOCT intensity signal based on defocus function and contrast agent absorption. By measuring the parameters of defocus function and contrast agent absorption, we compensate intensity fluctuation of each A-line caused by defocus and contrast agent absorption effects in IVOCT imaging. In clinical imaging, the proposed method improve the quality of IVOCT images and is helpful for plaque type identification. The average signal to noise ratio (SNR) of 200 images after compensation increase 6.5 dB than that before compensation.

Nd-doped ZnO thin films have been prepared by an electrodeposition method. The structure and the optical properties of the films were investigated. X-ray diffraction spectroscopy analysis indicates that the Nd doping can not disturb the structure of ZnO. No additional peaks are observed in the samples. The optical absorption spectra of Nd-doped ZnO thin films show that the absorbance peaks of the samples shift towards short wave length with the increase of Nd doping concentration. The photoluminescence spectra show that with the increase of concentration of Nd 3+ , visible emission is enhanced greatly and the intensity of ultraviolet emission is reduced.

The back-streaming neutron beam line (Back-n) was built in the beginning of 2018, which is part of the China Spallation Neutron Source (CSNS). The Back-n is the first white neutron beam line in China, and its main application is for nuclear data measurement. For most of neutron-induced nuclear reaction measurements based on white neutron facilities, the beam of gamma rays accompanied with neutron beam is one of the most important experimental backgrounds. The back streaming neutron beam is transported directly from the spallation target to the experimental station without any moderator or shielding, the flux of the in-beam gamma rays in the experimental station is much larger than those of these facilities with neutron moderator and shielding. Therefore, it is necessary to consider the influence of in-beam gamma rays on the experimental results. Studies of the in-beam gamma rays are carried out at the back-n. Monte-Carlo simulation is employed to obtain the energy distribution and the time structure of the in-beam gamma rays. According to the simulation results, when the neutron flight time is longer than 1.0 μs the energy distribution of the in-beam gamma rays does not vary with flight time. Therefore, the time structure of these gamma rays can be measured without the correction of the detection efficiency. In this work, the time structure of the in-beam gamma rays in the low neutron energy region is measured by both direct and indirect methods. In the direct measurement, a 6Li loaded ZnS(Ag) scintillator is located on the neutron beam line and the time of flight method is used to determine the time structure of neutrons and gamma rays. The gamma rays are separated from neutrons with pulse-shape discrimination. The black filter method is used to verify the particle discrimination results. In the indirect measurement, the C6D6 scintillation detectors are used to measure the gamma rays scattered off a Pb sample on the way of the neutron beam. The time structure of the in-beam gamma rays is derived from that of the scattered gamma rays. The experimental results are in good agreement with the simulations with the time-of-flight between 12 μs and 2.0 ms. Besides, according to the simulation results, the intensity of the in-beam gamma rays is 1.21 × 106 s–1·cm–2 in the center of the experimental station 2 of Back-n, which is 76.5 m away from the spallation target of CSNS.

To explore the effects of joint inclination angle and the size on the mechanical properties and failure process of rock-like specimens, a series of uniaxial compression tests were carried out on rock-like specimens.The specimens are consist of two sizes and contain three parallel joints with various inclination angles. During testing, the variation characteristics of apparent strain field of specimens is recorded by digital image correlation (DIC) system. Testing results reveal the uniaxial compression strength of the specimen decreases gradually with the joint inclination increases from 0° to 60°, while increasing gradually with the joint inclination increases from 60° to 90°. In addition, the peak compression strength of the large-size specimens is obviously lower than that of the small-size specimen when the joint inclination angle is 0°~30°. By contrast, the peak compression strength of the large-size specimens is the same as that of the small-size specimen when the angle is 30°~60°, approximately. But, the peak compression strength of large-size specimen is obviously higher than that of small-size specimen when the joint inclination angle is between 60° and 90°. Finally, five different types of cracks are observed in this work, i.e., tensile crack,airfoil tension crack,pull-shear mixing crack,secondary crack and far field tensile crack.

Monitoring of farmland pests is an important prerequisite to sprinkle agriculture in a timely and appropriate manner, which provide an important guarantee for agricultural production. This paper presents a method for obtaining the dynamic characteristics of pests in farmland based on machine vision. First, the pests and the background images are segmented by color feature and thresholding methods. Then, the shape features and the number of pests were obtained by Gaussian filtering. Finally, the quantity of pest motion is obtained by frame-to-frame differencing method. The experimental results show that the accuracy rate of the experimental sample is 99%. It can provide quantitative information of pest activity for plant protection personnel. This system can also be applied in large-scale crop pest monitoring.

Super module assembled with MRPC detectors is the component unit of TOF (Time of Flight) system for the Compressed Baryonic Matter (CBM) experiment. Quality of super modules needs to be evaluated before it is applied in CBM-TOF. Time signals exported from super module are digitalized at TDC (Time to Digital Converter) station. Data rate is up to 6 Gbps at each TDC station, which brings a tremendous pressure for data transmission in real time. In this paper, a real-time data flow control method is designed. In this control method, data flow is divided into 3 types: scientific data flow, status data flow and control data flow. In scientific data flow, data of each TDC station is divided into 4 sub-flows, and then is read out by a parallel and hierarchical network, which consists of multiple readout mother boards and daughter boards groups. In status data flow, status data is aggregated into a specific readout mother board. Then it is uploaded to DAQ via readout daughter board. In control data flow, control data is downloaded to all circuit modules in the opposite direction of status data flow. Preliminary test result indicated data of STS was correctly transmitted to DAQ with no error and three type data flows were control orderly in real time. This data flow control method can meet the quality evaluation requirement of supper module in CBM-TOF.

There are several spectrometers in White Neutron Source of China Spallation Neutron Source (CSNS-WNS) including detectors of C6D6, Silicon, fission chamber and light charged particle etc. Matching signals from these various detectors becomes design challenge for readout electronics design. In this paper, a generalized readout structure based on PXIe platform is proposed. Signal conditioning module named SCM plays important role in connecting signals from various detectors to a uniform readout system. SCM can be adapted to a variety of detectors by parameter adjustment. Test results show that this SCM has a good performance, which meets the requirement of detectors at CSNS- WNS.

In this study, the complete mitochondrial genome of Pagetopsis macropterus was obtained, which was 17,342 bp including 2 ribosomal RNAs, 13 protein-coding genes, 22 transfer RNAs, and one control r...

Mn-doped ZnO nanocrystal was prepared on Si substrates by cathodic electrodeposition. X-ray diffraction (XRD) study suggests that the Mn ions are substituted for Zn position into ZnO crystal. Field-emission scanning electron microscopy (SEM) images show the column-like morphology of ZnO nanocrystal. In photoluminescence spectrum, the visible emission band is broadened because of the doping effect. The fitted result of the temperature-dependent PL spectra in the range from 122.8 K to 302.2 K indicates that Mn dopant could lead to the decrease of the exciton binding energy.

Inter-symbol interference (ISI) in visible light communication (VLC) systems has been considered as a major problem which seriously deteriorates system performance. Constant modulus algorithm (CMA) is a widely adopted blind equalization scheme to eliminate ISI in practice due to its computational simplicity and effectiveness. This paper proposed an initialization scheme for CMA based on received signal power. The similarity level of the channels is measured by the difference between the current received power and the pre-stored received power. If the difference appears in a specific range, the pre-stored weight vector already calculated can be used for initialization. Compared with the center-spike initial setting, the proposed scheme can accelerate the convergence rate of CMA and ensure that the equalizer will converge to a stable equilibrium near a desired global minimum.

A copper(I)-catalyzed ring-opening cyanation of cyclopropanols was developed. The reaction provides an alternative method to achieve β-cyano ketones efficiently. This reaction exhibits good functional group compatibility under mild conditions and can be scaled up to the gram scale. Preliminary mechanistic studies suggest that the reaction might go through a free radical process.

Substantial experimental and theoretical efforts worldwide are devoted to explore the phase diagram of strongly interacting matter. At LHC and top RHIC energies, QCD matter is studied at very high temperatures and nearly vanishing net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was created at experiments at RHIC and LHC. The transition from the QGP back to the hadron gas is found to be a smooth cross over. For larger net-baryon densities and lower temperatures, it is expected that the QCD phase diagram exhibits a rich structure, such as a first-order phase transition between hadronic and partonic matter which terminates in a critical point, or exotic phases like quarkyonic matter. The discovery of these landmarks would be a breakthrough in our understanding of the strong interaction and is therefore in the focus of various high-energy heavy-ion research programs. The Compressed Baryonic Matter (CBM) experiment at FAIR will play a unique role in the exploration of the QCD phase diagram in the region of high net-baryon densities, because it is designed to run at unprecedented interaction rates. High-rate operation is the key prerequisite for high-precision measurements of multi-differential observables and of rare diagnostic probes which are sensitive to the dense phase of the nuclear fireball. The goal of the CBM experiment at SIS100 (sNN= 2.7--4.9 GeV) is to discover fundamental properties of QCD matter: the phase structure at large baryon-chemical potentials (μB> 500 MeV), effects of chiral symmetry, and the equation of state at high density as it is expected to occur in the core of neutron stars. In this article, we review the motivation for and the physics programme of CBM, including activities before the start of data taking in 2024, in the context of the worldwide efforts to explore high-density QCD matter.

Aims The study was undertaken to reveal the effects of disturbance on carbon, nitrogen and soil fungi distribution patterns in Napahai wetland. Methods Changes in soil carbon and nitrogen and ecological characteristics of soil fungi were studied across wetlands of varying levels of disturbance, including primitive marsh (non-disturbance), swampy meadow (low disturbance), meadow (moderate disturbance), and cultivated wetland (high disturbance). Important findings (1) In both upper and lower soil layers, soil organic matter (SOM), total nitrogen (TN), C:N and pH significantly differed (p < 0.01) among the four wetland types; SOM and TN decreased with increasing level of disturbance. (2) Following the culture on PDA medium, the abundance of soil fungi was greater in the upper layer than in the lower layer within the same type of wetland soil; with increasing level of disturbance, the abundance of fungi gradually increased, and the abundance of fungi was negatively correlated with pH value, SOM and TN, and positively correlated with C:N (2-tail test, p < 0.05). (3) Phylogenetic analysis shows that the soil fungi in Napahai wetland occur as Ascomycota, Basidiomycota, and Zygomycota, with Ascomycota being the dominant type and playing a key role in decomposition of soil carbon and nitrogen in plateau wetland.

A low-noise and fast preamplifier is needed for the new boron-coated multiwire proportional chamber (MWPC) neutron detector with a delay line readout system to improve position resolution. A transimpedance preamplifier with a rise time of 30ns, a signal-to-noise ratio higher than 40dB, and an automatic gain control function are designed to meet the aforementioned requirements. On the other hand, we also compare it to commercial preamplifiers. Then, the advantages and disadvantages of commercial and in-house preamplifiers are analyzed. The preamplifier is used and tested on a MWPC neutron detector, and results are presented.

Different from other electronics measurement, the bandwidth of the instrument can affect the test results more seriously in jitter and bit-error rate (BER) test. This paper analyzes the effect on the jitter and BER test results caused by instrument bandwidth in high-speed serial interconnection. An algorithm is presented to measure and estimate the equivalent frequency response of instruments. Computed data-dependent jitter (DDJ) results are produced based on the S-parameter of the serial interconnected channels and the equivalent frequency response of instruments, which are perfectly consistent with actual DDJ measure results. These methods can be used to measure and calibrate the instrument bandwidth effect precisely in jitter and BER test. At last, the paper gives the results of the instrument bandwidth effect for three channels and a set of instruments according to simulation, and presents a new concept “equivalent bandwidth” to roughly estimate the test error of DDJ caused by instrument bandwidth.

A marine seismic prospecting system is a kind of data acquisition and transmission system with large-scale coverage and synchronous multi-node acquisition. In this kind of system, data transmission is a fundamental and difficult technique. In this paper, a high-speed data-transmission method is proposed, its implications and limitations are discussed, and conclusions are drawn. The method we propose has obvious advantages over traditional techniques with respect to long-distance operation, high speed, and real-time transmission. A marine seismic system with four streamers, each 6000 m long and capable of supporting up to 1920 channels, was designed and built based on this method. The effective transmission baud rate of this system was found to reach up to 240 Mbps, while the minimum sampling interval time was as short as 0.25 ms. This system was found to achieve a good synchronization: 83 ns. Laboratory and in situ experiments showed that this marine-prospecting system could work correctly and robustly, which verifies the feasibility and validity of the method proposed in this paper. In addition to the marine seismic applications, this method can also be used in land seismic applications and certain other transmission applications such as environmental or engineering monitoring systems.

The process of amyloid formation is cytotoxic and contributes to a wide range of human diseases, but the mechanisms of amyloid-induced cytotoxicity are not well understood. It has been proposed that amyloidogenic peptides exert their toxic effects by damaging membranes. Membrane disruption is clearly not the only mechanism of toxicity, but the literature suggests that loss of membrane integrity may be a contributing factor. In this chapter we describe the measurement of in vitro membrane leakage induced by amyloidogenic proteins via the use of model vesicles. We use islet amyloid polypeptide (IAPP, amylin) as an example, but the methods are general.

Amyloid formation and aberrant protein aggregation are hallmarks of more than 30 different human diseases. The proteins that form amyloid can be divided into two structural classes: those that form compact, well-ordered, globular structures in their unaggregated state and those that are intrinsically disordered in their unaggregated states. The latter include the Aβ peptide of Alzheimer's disease, islet amyloid polypeptide (IAPP, amylin) implicated in type 2 diabetes and α-synuclein, which is linked to Parkinson's disease. Work in the last 10 years has highlighted the potential role of pre-amyloid intermediates in cytotoxicity and has focused attention on their properties. A number of intrinsically disordered proteins appear to form helical intermediates during amyloid formation. We discuss the spectroscopic methods employed to detect and characterize helical intermediates in homogenous solution and in membrane-catalyzed amyloid formation, with the emphasis on the application of circular dichroism (CD). IAPP is used as an example, but the methods are generally applicable.

Substantial experimental and theoretical efforts worldwide are devoted to explore the phase diagram of strongly interacting matter. At LHC and top RHIC energies, QCD matter is studied at very high temperatures and nearly vanishing net-baryon densities. There is evidence that a Quark-Gluon-Plasma (QGP) was created at experiments at RHIC and LHC. The transition from the QGP back to the hadron gas is found to be a smooth cross over. For larger net-baryon densities and lower temperatures, it is expected that the QCD phase diagram exhibits a rich structure, such as a first-order phase transition between hadronic and partonic matter which terminates in a critical point, or exotic phases like quarkyonic matter. The discovery of these landmarks would be a breakthrough in our understanding of the strong interaction and is therefore in the focus of various high-energy heavy-ion research programs. The Compressed Baryonic Matter (CBM) experiment at FAIR will play a unique role in the exploration of the QCD phase diagram in the region of high net-baryon densities, because it is designed to run at unprecedented interaction rates. High-rate operation is the key prerequisite for high-precision measurements of multi-differential observables and of rare diagnostic probes which are sensitive to the dense phase of the nuclear fireball. The goal of the CBM experiment at SIS100 (sqrt(s_NN) = 2.7 - 4.9 GeV) is to discover fundamental properties of QCD matter: the phase structure at large baryon-chemical potentials (mu_B > 500 MeV), effects of chiral symmetry, and the equation-of-state at high density as it is expected to occur in the core of neutron stars. In this article, we review the motivation for and the physics programme of CBM, including activities before the start of data taking in 2022, in the context of the worldwide efforts to explore high-density QCD matter., 15 pages, 11 figures. Published in European Physical Journal A

According to the investigations of biological resources in Lake Taihu during 2006-2007,we calculated that total fishery yield potential of phytoplankton,zooplankton,zoobenthos and aquatic macrophytes in Lake Taihu was about 78494t.In order to increase fish yields and inhibit cyanobacteria bloom in Lake Taihu,stocking number of silver carp(Hypohthalmichthys molitrix Richardson) and bighead carp(Aristichthys nobilis Cuvier) should be increased to 10 million and 3 million tails,respectively,and the specification should be 20 tails per kilogram.To protect resources of aquatic macrophytes and zoobenthos,the reasonable stocking number of grass carp(Ctenopharyngodon idellus Cuvier),blunt snout bream(Megalobrama amblycephala Yih),black carp(Mylopharyngodon piceus Richardson) and common carp(Cyprinidae carpio Linnaeus)should be 1.5 million,1.65 million,80-100 thousand and 25 million tails,respectively.As topmouth cutler such as cutler alburnus could play important roles in controlling miniaturization and singleness of fishery structure and increase added-value of fishery economy,its stocking quantity should be increased to 5 million tails.

The hormone human islet amyloid polypeptide (hIAPP or amylin) plays a role in glucose metabolism, but forms amyloid in the pancreas in type 2 diabetes (T2D) and is associated with β-cell death and dysfunction in the disease. Inhibitors of islet amyloid have therapeutic potential; however, there are no clinically approved inhibitors, and the mode of action of existing inhibitors is not well understood. Rat IAPP (rIAPP) differs from hIAPP at six positions, does not form amyloid, and is an inhibitor of amyloid formation by hIAPP. Five of the six differences are located within the segment of residues 20-29, and three of them are Pro residues, which are well-known disruptors of β-sheet structure. rIAPP is thus a natural example of a "β-breaker inhibitor", a molecule that combines a recognition element with an entity that inhibits β-sheet formation. Pramlintide (PM) is a peptide drug approved for use as an adjunct to insulin therapy for treatment of diabetes. PM was developed by introducing the three Pro substitutions found in rIAPP into hIAPP. Thus, it more closely resembles the human peptide than does rIAPP. Here we examine and compare the ability of rIAPP, PM, and a set of designed analogues of hIAPP to inhibit amyloid formation by hIAPP, to elucidate the factors that lead to effective peptide-based inhibitors. Our results reveal, for this class of molecules, a balance between the reduced amyloidogenicity of the inhibitory sequence on one hand and its ability to recognize hIAPP on the other.

The Co-doped ZnO film was grown by electrodeposition method,the carrier concentration is 1017 cm-3,but the sample is paramagnetism.The electrons can not induce the room temperature ferromagnetism,only the introducing of additional carriers can enhance the ferromagnetic exchange action and induce the room temperature ferromagnetism.Nitrogen-doped ZnCoO film was obtained in plasma-enhanced chemical vapor deposition system,where NH3 plasma provided N source.After an ammine plasma treatment the room tempe-rature ferromagnetism was detected on ZnCoO sample.So some holes generated by N doping play an important role for the room temperature ferromagnetic properties in Co doped ZnO sample.In our experiments,although the sample still is n-type semiconductor,there are some holes in the crystal generated by plasma treatment.In this theory,a bound magnetic polarons(BMPs) could be formed after the introduction of p-type dopant N.

Hydrogen fuel produced by photovoltaic-eletrolyzer system is a solution to solve problem of global warming, air pollution and fossil fuel crisis. The efficiency of photovoltaic-electrolyzer system can be promoted by the optimal matching between photovoltaic modules and electrolyzer. Based on experimental test and mathematical model, a certain series–parallel connection of photovoltaic cells is determined to match with electrolyzer. The aim is to match the voltage and the maximum power output of the photovoltaic modules to the operating voltage of the electrolyzer. So some auxiliaries such as DC-DC converter, maximum power point (MPP) tracking unit can be omitted. Therefore, the cost and resistances in the circuit are greatly reduced.

In order to improve the accuracy of the fiber Bragg grating demodulation system,a denoising processing and filtering analysis method based on empirical mode decomposition is proposed.The intrinsic mode functions obtained by EMD are derived into signal component dominanting modes and noise component dominanting modes.Denoising can be achieved by reconstructing the signal using the modes reflecting the main structures of the signal.The experimental results show that the output signal of demodulation system can achieve identitfying the location of central wavelength and the Bragg wavelength shift accurately.The output spectrum has the features of less distortion and higher SNR.The curve fitting of temperature shows that the fitting linearity is 0.998,and the accuracy of demodulation system is greatly improved.

Fishery is one of the main functions of Lake Taihu,which plays an important role in improving the water environment. However,it is also influenced to a large degree by the environmenal change.Recently,the main problems facing the natural fishery in Lake Taihu are the over-intensive catching and irrational utilization of natural resources.This paper,based on the data of many years' catches in Lake Taihu,analyzed the community structure of fishes in Lake Taihu and their succession dynamics.According to the fish yields and compositions in different area of Lake Taihu,the natural fishery characteristics and problems were studied.Some ideas were presented to develop the natural fishery based on the present research,such as controlling the fishing gear specifications and catching intensity,adjusting the catching time,regulating the structure and proportion of stocking fish species and developing lake fishery in a reasonable way.Meanwhile,the potential of natural fishery was analyzed on the basis of present biological resources in Lake Taihu.It suggested that the construction of fishery environment and studies on influence of fishery on water environment should be strengthened for the further development of lake fishery.

During April in 2004 and November and October in 2005,based on the food composition investigation for 263 food samples of Neosalanx tangkahkeii taihuensis Chen and Coilia ectenes taihuensis Yen et Lin and the cor- relative analysis of the changes of fish catches,the food relationship and the mutual effects between the two fishes were studied in Lake Taihu.Results showed that:Neosalanx tangkahkeii taihuensis Chen mainly fed on Copepoda accounting for 70.11%±10.57% in its food,Cladocera accounting for 29.84%±10.62% and Rotifera only ac- counting for 0.05%±0.11% in the investigation during April;while in the same time investigation,Coilia ectenes taihuensis Yen et Lin mainly fed on Cladocera accounting for 79.35%±11.42% in its food,Copepoda accounting for 19.97%±10.78%,and Rotifera and shrimp respectively accounting for 0.49%±0.45% and 0.20%±0.44% and in the investigation during November and October;Cladocera accounted for 89.77%±13.69% in its food,Copepeda accounted for 7.84%±11.53% ,and Rotifera only accounted for 2.39%±4.95%.The average food overlap coefficient in 5 sampling points between the two fishes was 0.4739±0.2810 which did not reached to the significant overlap level during the April investigation.The resemble food composition was 46.42%±20.32%. The partial correlative analysis showed that:there was negative correlation between the catches of the two fishes, but not significant;there was the trend of the significant level of the negative correlation getting high and high with the catches of the two fishes increasing.For example,the significant level of the negative correlation was r=- 0.4395 p=0.101 during the periods from 1973 to 1984 and was r=-0.4395 p=0.101 during the periods from 1985 to 2004.The analysis might show that:the main food of the two fishes was different so that in common ecolog- ical conditions there was nearly not fiercely food competition between the two fishes.But with their density getting high there would be food competition between them and the food competition was mainly focused on the Copepoda.

From September to December in 2004,based on the food content investigation,the food relationship and the mutual effects between Coilia ectenes taihuensis Yen et Lin and Hypophthalmichthys molitrix(Cuvier et Valenci- ennes)and Aristichthys nobilos(Richardson)were studied in Lake Taihu.Results showed that:Cyanobacteria oc- cupied over 90% of food volume in alimentary canal of Hypophthalmichthys molitrix(Cuvier et Valenciennes)and Aristichthys nobilos(Richardson),about 15%-35% of food volume in alimentary canal of Coilia ectenes taihuensis Yen et Lin;Hypophthalmichthys molitrix(Cuvier et Valenciennes)and Aristichthys nobilos(Richardson)basicly fed on the same food.Except Cyanobacteria,Coilia ectenes taihuensis Yen et Lin mainly fed on Cladocera account- ing for 89.77%±13.69%,Copepoda accounting for 7.84%±11.53% and Rotifera accounting for 2.39%±4.95%.Hypophthalmichthys molitrix(Cuvier et Valenciennes)and Aristichthys nobilos(Richardson)nearly fed on the same species of Cladocera as that of Coilia ectenes taihuensis Yen et Lin.The partial correlative analysis showed that:there was negative correlation between the catches of Coilia ectenes taihuensis Yen et Linand the cat- ches of Hypophthalmichthys molitrix(Cuvier et Valenciennes)and Aristichthys nobilos(Richardson)at the signifi- cant lever of p＜0.05.

The instability of the pillar was discussed based on the potential energy principle and the cusp catastrophe theory, and a simplified mechanical model of the pillar was established considering the mining effect. The necessary-sufficient conditions, the jump value of displacement of pillar and the released energy expressions were deduced. The results show that the instability of the pillar is related to the properties of the rock, the external force and the relative stiffness of the elastic area to the plastic area. The instability of system is like to occur with the enlarging of the softening area or the decreasing of E/λ. The calculation done shows that the estimated results correspond to practical experience.

The authors used selenium-enriched vegetables as test materials during research on juice production. The purpose of this study is to provide a basis for developing a practical processing technology. The changing regularity of two quality attributes on three Se-enriched green-leafy vegetable juices was studied during juice making. The effects of processing conditions on chlorophyll contents, total Se content and organic Se percentage were measured. The difference of enriching with zinc between pre-harvest and post-harvest, chlorophyll preservation and separation during storage of combined juices have been discussed. The results show that the effect of blanching on total selenium content is far more severe than the effect of sterilization. However, the effect of the process of sterilization on organic selenium percentage is far more severe than the effect of blanching. The range of ZnCl2 content that was sprayed by the process of agronomic Zn-enrichment before production is 1200–1400 μg/ml. By means of color preservation, chlorophyll in combined vegetable juices can be preserved almost the same as that of single vegetable juice. Alginate–Na has an effective action in preventing sedimentation in combined vegetable juice.

A detailed analysis of mode II stress intensity factors(SIFs) for the double edge cracked Brazilian disk subjected to different diametral compression is presented using a weight function method. The model II SIFs at crack tips can be obtained by simply calculating an integral of the product of mode II weight function and the shear stress on the prospective crack faces of uncracked disk loaded by a diametral compression. A semi-analytical formula for the calculation of normalized mode II SIF, fII, is derived for different crack lengths (from 0.1 to 0.7) and inclination angles (from 10° to 75°) with respect to loading direction. Comparison between the obtained results and finite element method solutions shows that the weight function method is of high precision. Combined with the authors’ previous work on mode I fracture analysis, the new specimen geometry can be used to study fracture through any combination of mode I and mode II loading by a simple alignment of the crack relative to the diameter of compression loading, and to obtain pure mode II crack extension. Another advantage of this specimen geometry is that it is available directly from rock core and is also easy to fabricate.

A new specimen geometry—the double edge-cracked Brazilian disk and a relevant fracture analysis by weight function method are proposed for the investigation of rock fracture caused by compression-shear loading. Not only can the mixed mode fracture with any ratio of KI/KII be achieved, but also the pure mode II crack extension can be obtained. The combined mode fracture analysis for this geometry shows that diametral compression in the farfield can induce a compression-shear stress state in the singular stress field ahead of crack tips. Experimental investigations conducted on marble specimens show that the pure mode II crack extension can be obtained when the dimensionless crack length a>0.7 and the inclined crack angle 5°⩽ϕ⩽40°. Normalized mode I and mode II stress intensity factors decrease from −0.45 and 2.47 at ϕ=5° to −1.65 and 1.52 at ϕ=40°, respectively. The strains at three points of specimen are also measured in order to investigate the influence of stress singularity on initial crack extension. The results show that the principal orientations of strain at three points are very stable in the loading process. The derived formulae are quite explicit, and the specimen geometry is easy to fabricate and convenient to achieve the pure mode II crack extension. Therefore, it can hopefully be used to obtain mode II fracture toughness of rock.

Software testing is aimed to improve the delivered reliability of the users. Delivered reliability is the reliability of using the software after it is delivered to the users. Usually the software consists of many modules. Thus, the delivered reliability is dependent on the operational profile which specifies how the users will use these modules as well as the defect number remaining in each module. Therefore, a good testing policy should take the operational profile into account and dynamically select tested modules according to the current state of the software during the testing process. This paper discusses how to dynamically select tested modules in order to maximize delivered reliability by formulating the selection problem as a dynamic programming problem. As the testing process is performed only once, risk must be considered during the testing process, which is described by the tester's utility function in this paper. Besides, since usually the tester has no accurate estimate of the operational profile, by employing robust optimization technique, we analysis the selection problem in the worst case, given the uncertainty set of operational profile. By numerical examples, we show the necessity of maximizing delivered reliability directly and using robust optimization technique when the tester has no clear idea of the operational profile. Moreover, it is shown that the risk averse behavior of the tester has a major influence on the delivered reliability., Comment: 19 pages, 4 figures

An automatic clock synchronization method implemented in a field programmable gate array (FPGA) is proposed in this paper. It is developed for the clock system which will be applied in the end-cap time of flight (ETOF) upgrade of the Beijing Spectrometer (BESIII). In this design, an FPGA is used to automatically monitor the synchronization circuit and deal with signals coming from the external clock synchronization circuit. By testing different delay time of the detection signal and analyzing the signal state returned, the synchronization windows can be found automatically by the FPGA. The new clock system not only retains low clock jitter which is less than 20ps root mean square (RMS), but also demonstrates automatic synchronization to the beam bunches. So far, the clock auto-synchronizing function has been working successfully under a series of tests. It will greatly simplify the system initialization and maintenance in the future.

This paper deals with two of the most important and difficult aspects of portable planar broadband antennas: the ground plane effects and measurements. To minimize the ground plane effects, optimized slots are created on the ground plane to limit the current flow hence the ground plane effects, which is demonstrated to be a simple but effective approach. For the antenna measurement, our focus is on how to measure the antenna radiation efficiency accurately and efficiently. Two of the latest methods, reverberation chamber and source stirred chamber/cap methods, are employed and discussed. Both numerical and experimental results are presented to aid our analyses and discussions.

In those traditional ways of treating alkali weight reduction wastewater, the COD removal is greatly considered, while recovering the valuable resource according to the principles of sustainable development is less involved. In this study, the recovery of high pure TA from alkali weight-reduction has been researched by purified mother liquid with coagulation sedimentation. The characters of TA obtained was investigated by various methods, results has shown that the purity of TA was great improved in view of high recovery rate by coagulation sedimentation on conditions of pH 7.0-7.5 of wastewater and 300-400mg/l in quantity of Al2(SO4)3.18H2O, thermogravimetric analysis (TGA) spectrums proved this. Particle size analysis revealed the crystal size of recovered TA became greater, it contained few impurities. So coagulation-sedimentation by pretreatment is an effective method. The study is also very useful in recycling of PET and treating TA industrial wastewater.