Search

Abstract: A novel mixotrophic biofilm reactor (MBR) was operated to simultaneously remove total organic carbon, nitrate, and Mn(II). Effects of some key factors on mixotrophic denitrification were investigated in lab‐scale bioreactors. Optimized conditions obtained from the MBR were used to validate the experiments, proving their feasibility. High‐throughput sequencing was employed to analyze the microbial communities of the MBR. The community diversity in the MBR was markedly influenced by the ratio of Cinorganic:Corganic. The species were increased with lower Cinorganic:Corganic concentration. Pseudomonas was detected as the dominant species in the MBR, indicating that Pseudomonas sp. SZF15 and Pseudomonas sp. H‐117 play a primary role in the process of nitrate removal. [ABSTRACT FROM AUTHOR]

Nonlinear wave equation is extensively applied in a wide variety of scientific fields, such as nonlinear optics, solid state physics and quantum field theory. In this paper, two high-performance compact alternating direction implicit (ADI) methods are developed for the nonlinear wave equations. The first scheme is developed a three-level nonlinear difference scheme for nonlinear wave equations, where in x -direction, series of linear tridiagonal systems are solved by Thomas algorithm, while in y -direction, nonlinear algebraic system are computed by Newton’s iterative method. In contrast, the second scheme is linear, and permits the multiple uses of the Thomas algorithm in both x - and y -directions, thus it saves much time cost. By using the discrete energy analysis method, it is shown that both the developed schemes can attain numerical accuracy of order O ( τ 4 + h x 4 + h y 4 ) in H 1 -norm. Meanwhile, by the fixed point theorem and symmetric positive-definite properties of coefficient matrix, it is proved that they are both uniquely solvable. Besides, the proposed schemes are extended to the numerical solutions of the coupled sine-Gordon wave equations and damped wave equations. Finally, numerical results confirm the convergence orders and exhibit efficiency of our algorithms. [ABSTRACT FROM AUTHOR]

Abstract: O6‐Corona[3]arene[3]pyridazines were synthesized from the one‐pot macrocyclic condensation reaction of 3,6‐dichlorotetrazine with 1,4‐dihydroquinone derivatives followed by the inverse electron demand Diels‐Alder reaction of the tetrazine rings with a cyclopentanone‐derived enamine. Conversion of six ester groups within macrocycle into all sodium acetate moieties afforded a water soluble O6‐corona[3]arene[3]pyridazine. The coronary macrocycle host formed complexes selectively with organic ammoniums and dinitrile guests in a 1: 1 stoichiometric ratio in organic solvents with association constants ranging from (2.96 ± 0.10) × 101 to (2.53 ± 0.33) × 105 L·mol−1. Water soluble O6‐corona[3]arene[3]pyridazine was also able to complex strongly with organic ammoniums in water to give an association constant up to (2.67 ± 0.21) × 104 L·mol−1. The pseudo‐rotaxane and inclusion structures of the host‐guest complexes were revealed by the X‐ray crystallography. [ABSTRACT FROM AUTHOR]

It is of importance to develop efficient high-order solution-flux domain decomposition methods for solving the large scale time-dependent partial differential equations. In this paper, a fourth-order compact block-centered splitting domain decomposition method is developed for solving parabolic partial differential equations in large domains. Combining the time second-order splitting technique with non-overlapping domain decompositions, we propose the compact block-centered splitting domain decomposition algorithm to the solution-flux structured system of parabolic partial differential equations. The domain is divided into non-overlapping multi-block sub-domains of block-centered meshes. On the interfaces of sub-domains, the interface fluxes are predicted by the semi-implicit interface flux scheme while the solution and flux in the interiors of sub-domains are computed by the compact block-centered implicit solution-flux scheme. The feature of the method is that over block-centered grids, constructing high-order compact difference scheme to the structured system of solution and flux equations leads to efficient schemes for solving the problems over domain decompositions. Numerical experiments show that the method is of fourth-order convergence in space and of second order convergence in time and it is much efficient in parallel computing. [ABSTRACT FROM AUTHOR]

A new adjustable and combined reinforcement method consisting of arch rib and steel beam is proposed in this paper. The principle is to redistribute the internal forces of the structure through the support of the arch rib and to form a combined structure by using steel and concrete. Symmetrically loaded bending tests were carried out with five different combined strengthening schemes. The analysis of the test process was conducted adopting a FEM model, and the equations for calculating the RC beam's load capacity under combined strengthening were derived while considering the slip effect. The experimental results indicated that the combined reinforcement method had a synergistic effect when the ultimate load capacity had increased by more than 95% after reinforcement. As the size of the arch ribs and profile beams increased, a better reinforcement effect was seen. However, beyond a certain range, the RC beams had already broken down and had failed before the reinforcement material could yield. The combined reinforcement method changes the force system of the original RC beam, resulting in a smaller angular inclination trend of the cracks in the original purely curved section and a smaller crack extension. The non-linear finite element results are generally consistent with experimental loads, displacements, and ductility, while the average ratio of experimental to calculated ultimate Load capacity is 0.95, demonstrating that non-linear finite elements and theoretical formulas are accurate. [ABSTRACT FROM AUTHOR]

One common application of pressure swing adsorption technology is medical oxygen concentrator (MOC) which directly produces ~ 94% O2 from air. The operating condition determines the separation efficiency of MOC and is varied with practical requirements. A better understanding of performance, mass and heat transfer inside adsorption bed at wide operating conditions is of great importance. The impacts of key operating parameters on the performances, the concentration and temperature distributions of MOC have been numerically investigated. The numerical results demonstrate that high comprehensive performances are achieved at an optimal condition with combination of adsorption pressure, product and feed flowrate and feed temperature. As adsorption pressure increases, the front of gas concentration and temperature becomes sharp, which effectively benefits for improving the performance. It is nearly identical shapes of nitrogen concentration and gas temperature profiles after adsorption and the profiles are pushed forward near production end with increasing of product flowrates and decreasing of feed flowrates. The increasing of feed temperature is beneficial to improve the performance. However, the adverse mass transfer and thermal effects are dominant at very high pressures, flowrates and temperatures conditions and this variation increases the unit power of MOC. [ABSTRACT FROM AUTHOR]

To research the dynamic response characteristics of the multi-link complex mechanism with lubricated clearance joint, an improved transitional lubrication model considering the roughness of the contact surface is established based on the fuzzy set model of the lubrication state. The dynamic model of a six-bar rocking feeding mechanism with lubricated clearance joint is established, and the influence of dry friction clearance and lubricated clearance on the dynamic response of the mechanism are analyzed. By comparing with the simulation results of ADAMS and Flores lubrication model, the correctness and effectiveness of the established dynamic model and the improved transition lubrication model are verified. The influence of driving speed, clearance size and number of clearances on the dynamic response of the mechanism with lubricated clearance joint is mainly studied. The simulation results show that the driving speed, clearance size and number of clearances have an impact on the dynamic characteristics of the mechanism. With the increase of driving speed and clearance value, the greater the impact on the mechanism, the increase in the number of clearances, which reduces the stability of the mechanism, and there is interaction between different clearance joints. [ABSTRACT FROM AUTHOR]

In this paper, we propose and analyze a finite difference method for the nonlinear Schrödinger equations on unbounded domain by using artificial boundary conditions. Two artificial boundary conditions are introduced to restrict the original Schrödinger equations on an unbounded domain into an initial–boundary value problem with a bounded domain. Then, a finite difference scheme for the reduced problem is proposed. The important feature of the proposed scheme is that an extrapolation operator is introduced to treat the nonlinear term while the scheme keeps unconditionally stable and does not introduce any oscillations at the artificial boundaries. The proposed scheme with the discrete artificial boundary conditions is rigorously analyzed to yield the unconditional stability and the scheme is also proved to be convergent. Numerical examples are given to show the performance of our scheme. [ABSTRACT FROM AUTHOR]

A real-time photonic sampling structure with effective nonlinearity suppression and excellent signal-to-noise ratio (SNR) performance is proposed. The key points of this scheme are the polarization-dependent modulators (P-DMZMs) and the sagnac loop structure. Thanks to the polarization sensitive characteristic of P-DMZMs, the differences between transfer functions of the fundamental signal and the distortion become visible. Meanwhile, the selection of specific biases in P-DMZMs is helpful to achieve a preferable linearized performance with a low noise level for real-time photonic sampling. Compared with the quadrature-biased scheme, the proposed scheme is capable of valid nonlinearity suppression and is able to provide a better SNR performance even in a large frequency range. The proposed scheme is proved to be effective and easily implemented for real time photonic applications. [ABSTRACT FROM AUTHOR]

High-speed robots are being applied more and more widely in the scenarios of aviation manufacturing, electronic packaging, and three-dimensional printing, etc. To achieve high speed, the robots are typically designed to be lightweight, hence suffer from undesired vibration, so that the dynamic performance would deteriorate. In light of this, this paper considers the dynamic modeling and active control of an emerging redundant parallel robot. First, the recursively dynamic model is modularly established by means of Lagrangian multipliers method. For completeness, the model of permanent magnet synchronous motor is further integrated with the model of mechanical system to formulate the electromechanically coupled dynamic model (ECDM). To facilitate dynamic control, the ECDM is cleverly projected into the null space of constraint Jacobian matrix eliminating the need to compute Lagrangian multipliers explicitly. Based on singular perturbation approach and Tikhonov theorem, the ECDM is decomposed into two subsystems in different timescales. On this basis, a nonlinear hybrid control scheme is proposed for both trajectory tracking and vibration suppression. Numerical simulations suggest that the nonlinear hybrid control exhibits overwhelming performance than the conventional joint-based proportional and differential feedback control. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of rigid-flexible coupling dynamic modeling and active control of a novel flexible parallel manipulator (PM) with multiple actuation modes. Firstly, based on the flexible multi-body dynamics theory, the rigid-flexible coupling dynamic model (RFDM) of system is developed by virtue of the augmented Lagrangian multipliers approach. For completeness, the mathematical models of permanent magnet synchronous motor (PMSM) and piezoelectric transducer (PZT) are further established and integrated with the RFDM of mechanical system to formulate the electromechanical coupling dynamic model (ECDM). To achieve the trajectory tracking and vibration suppression, a hierarchical compound control strategy is presented. Within this control strategy, the proportional-differential (PD) feedback controller is employed to realize the trajectory tracking of end-effector, while the strain and strain rate feedback (SSRF) controller is developed to restrain the vibration of the flexible links using PZT. Furthermore, the stability of the control algorithm is demonstrated based on the Lyapunov stability theory. Finally, two simulation case studies are performed to illustrate the effectiveness of the proposed approach. The results indicate that, under the redundant actuation mode, the hierarchical compound control strategy can guarantee the flexible PM achieves singularity-free motion and vibration attenuation within task workspace simultaneously. The systematic methodology proposed in this study can be conveniently extended for the dynamic modeling and efficient controller design of other flexible PMs, especially the emerging ones with multiple actuation modes. [ABSTRACT FROM AUTHOR]

I am honoured to address as the seventh president of the Mycological Society of China. Mycorrhizal research has a long history in China, including taxonomy, diversity, ecology, molecular biology, and application. Particularly in the past four decades, great progress in mycorrhizal field has been made by Chinese mycologists and ecologists. In this paper, through my own experience, I summarised the main and important advance of recent mycorrhizal researches in terms of mycorrhizal fungal diversity, community, responses to global environmental changes, molecular biology, and function in China. Some perspectives are also proposed for future mycorrhizal studies in China. [ABSTRACT FROM AUTHOR]

Evidence has shown that most hepatocellular carcinoma (HCC) cells are resistant to tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis. However, the molecular mechanisms underlying TRAIL-mediated apoptosis resistance are not well understood. In this study, we reported that downregulation of Decoy receptor 3 (DcR3) expression by lentiviral vectors carrying shRNA against DcR3 (LV-ShDcR3, shDcR3) in Huh7 both greatly enhanced TRAIL-mediated apoptosis and reduced cell proliferation capability. In addition, silencing DcR3 resulted in upregulation of the cell apoptotic regulators including Bid, caspase-3, and caspase-8. Caspase inhibitors inhibited shDcR3-mediated cell death, which indicated that downregulation of DcR3 expression in Huh7 cells increased TRAIL-induced caspase-dependent apoptotic cell death. Furthermore, although the knockdown of DcR3 altered the expression of some Bcl-2- and IAP-family proteins, this change was inhibited by pretreatment with a pancaspase inhibitor, which indicated the cytotoxic effect of shDcR3 was not due to the expression of these proteins. In contrast, shDcR3 significantly inhibited TRAIL-induced transcription factor nuclear κB (NF-κB) activation through the IκB kinase (IKK) pathway, as well as inhibited TRAIL-induced increases in FLICE-inhibitory protein long form (cFLIPL) expression at the transcriptional level. Silencing cFLIPL expression mimicked the cytotoxic effect of shDcR3 on TRAIL-mediated cell apoptosis. Moreover, overexpression of cFLIPL effectively prevented the increase in cell apoptosis in Huh7 cells co-treated with TRAIL and shDcR3. Taken together, our findings indicated that silencing DcR3 sensitizes TRAIL-mediated apoptosis in HCC cells by inhibiting NF-κB. [ABSTRACT FROM AUTHOR]

This paper presents a novel type of electromagnetic launch mode based on the similar principle of reconnection guns. The basic principle and launch model were introduced. Via the finite-element simulation, the electromagnetic force of the projectile is analyzed, and it has been found that this novel launch mode can accelerate the mass of 0.49 kg of the projectile to 680 m/s. After the slot, the performance of the launch mode has been further improved. The muzzle velocity of projectile achieved 707 m/s; meanwhile, the radial compression force becomes smaller. In addition, multipole field reconnection electromagnetic launcher can not only retain the advantage of the reconnection guns, but also has higher efficiency than traditional electromagnetic launcher. We proposed that this launch mode has an ideal application prospect especially in the field of big mass transportation and super-velocity launch. [ABSTRACT FROM AUTHOR]

To obtain an accurate count of wheat spikes, which is crucial for estimating yield, this paper proposes a new algorithm that uses computer vision to achieve this goal from an image. First, a home-built semi-autonomous multi-sensor field-based phenotype platform (FPP) is used to obtain orthographic images of wheat plots at the filling stage. The data acquisition system of the FPP provides high-definition RGB images and multispectral images of the corresponding quadrats. Then, the high-definition panchromatic images are obtained by fusion of three channels of RGB. The Gram-Schmidt fusion algorithm is then used to fuse these multispectral and panchromatic images, thereby improving the color identification degree of the targets. Next, the maximum entropy segmentation method is used to do the coarse-segmentation. The threshold of this method is determined by a firefly algorithm based on chaos theory (FACT), and then a morphological filter is used to de-noise the coarse-segmentation results. Finally, morphological reconstruction theory is applied to segment the adhesive part of the de-noised image and realize the fine-segmentation of the image. The computer-generated counting results for the wheat plots, using independent regional statistical function in Matlab R2017b software, are then compared with field measurements which indicate that the proposed method provides a more accurate count of wheat spikes when compared with other traditional fusion and segmentation methods mentioned in this paper. [ABSTRACT FROM AUTHOR]

In the theory of spontaneous combustion, identifying the critical value of the Frank-Kamenetskii parameter corresponds to solving a bifurcation point problem. There are two different numerical methods used to solve this problem—the direct and indirect numerical methods. The latter finds the bifurcation point by solving a partial differential equation (PDE) problem. This is a better method to find the bifurcation point for complex geometries. This paper improves the indirect numerical method by combining the grid-domain extension method with the matrix equation computation method. We calculate the critical parameters of the Frank-Kamenetskii equation for some complex geometries using the indirect numerical method. Our results show that both the curve of the outer boundary and the height of the geometries have an effect on the values of the critical Frank-Kamenetskii parameter, however, they have little effect on the critical dimensionless temperature. [ABSTRACT FROM AUTHOR]

We develop a multipoint flux mixed finite element method for the compressible Darcy–Forchheimer models. This method is motivated by the multipoint flux approximation method. Based on the lowest order Brezzi–Douglas–Marini mixed finite element method and combined with a special quadrature rule that allows for local velocity elimination and leads to a cell-centered system for the pressures. We develop two approximation methods for the problems, the semi-discrete method and fully discrete method, where the fully discrete method includes the backward Euler scheme and the Crank–Nicolson scheme. Theoretical results show the convergences for both pressure and velocity. The numerical experiments show that the convergence rates of the method are in agreement with the theoretical analysis. [ABSTRACT FROM AUTHOR]

Abundance and standard error estimates in surveys of fishery resources typically employ classical design-based approaches, ignoring the influences of non-design factors such as varying catchability. We developed a Bayesian approach for estimating abundance and associated errors in a fishery survey by incorporating sampling and non-sampling variabilities. First, a zero-inflated spatial model was used to quantify variance components due to non-sampling factors; second, the model was used to calibrate the estimated abundance index and its variance using pseudo empirical likelihood. The approach was applied to a winter dredge survey conducted to estimate the abundance of blue crabs ( Callinectes sapidus) in the Chesapeake Bay. We explored the properties of the calibration estimators through a limited simulation study. The variance estimator calibrated on posterior sample performed well, and the mean estimator had comparable performance to design-based approach with slightly higher bias and lower (about 15% reduction) mean squared error. The results suggest that application of this approach can improve estimation of abundance indices using data from design-based fishery surveys. [ABSTRACT FROM AUTHOR]

Polyacrylate polymer (PA) has been widely applied in coating products for decades. Recently, it has been used in controlled-release fertilizers. Nano Fe III -tannic acid modified PA (PA-Fe) provides a better nutrient controlled release performance than conventional PA. In this work, a preliminary database of molecular and elemental information about the polymer was obtained using FTIR-PAS (Fourier transform infrared photoacoustic spectroscopy) and LIBS (laser-induced breakdown spectroscopy), respectively. The PA-Fe polymer contained more hydrophobic groups (–CH 3 ) and fewer hydrophilic groups (–COOR, –COOH) than PA. More elements were detected for PA-Fe than PA. LIBS was useful to identify and classify PA and PA-Fe samples using principal component analysis. The combination of spectroscopic results and a film formation process model explained the lower nutrient release rate of PA-Fe. These results showed the strong analytical capabilities of FTIR-PAS combined with LIBS for identifying and characterizing modified PA. [ABSTRACT FROM AUTHOR]

Like all poikilotherms, the growth and reproduction of blue crab, Callinectes sapidus depends on temperature and season. Warmer water temperatures in the Chesapeake Bay allow for ovarian development and spawning, while colder water temperatures slow their metabolism and reproduction. The current study aimed to identify optimal environmental conditions for inducing reproduction in animals held in long-term captivity for year round production in aquaculture through environmental manipulations. Temperature and photoperiod were the main environmental factors tested for 25 weeks: 11°C and 21°C, with the following photoperiods: 0L:24D, 8L:16D, 16L:8D and 24L:0D. At 21°C, the females increased spawning frequency, which was arrested at 11°C. Shorter light exposure at 21°C increased spawning frequency, while constant light inhibited and did not produce spawning. Constant dark (0L:24D) at 21°C produced the most (86%) spawns, but yielded poor larval quality. At 21°C with all photoperiod conditions except constant light, the first spawning took 94.8 ± 32.4 days to occur ( n = 17). With females producing multiple spawns, the intervals between the first and second spawns and the second and third spawns were 37.7 ± 8.7 days ( n = 6) and 31.0 ± 7.1 days ( n = 2) respectively. Analysis of our data using response surface methodology ( RSM) predicts the following conditions: at 15-19°C and 0-10 hr darkness for maximal survival and at 19-22°C and 0-8 hr darkness for spawning. The number of larvae produced was positively correlated with size (weight) of the female C. sapidus, suggesting the importance of female size in reproduction. [ABSTRACT FROM AUTHOR]

A systematic dynamic modeling methodology is presented to develop the rigid-flexible coupling dynamic model (RFDM) of an emerging flexible parallel manipulator with multiple actuation modes. By virtue of assumed mode method, the general dynamic model of an arbitrary flexible body with any number of lumped parameters is derived in an explicit closed form, which possesses the modular characteristic. Then the completely dynamic model of system is formulated based on the flexible multi-body dynamics (FMD) theory and the augmented Lagrangian multipliers method. An approach of combining the Udwadia-Kalaba formulation with the hybrid TR-BDF2 numerical algorithm is proposed to address the nonlinear RFDM. Two simulation cases are performed to investigate the dynamic performance of the manipulator with different actuation modes. The results indicate that the redundant actuation modes can effectively attenuate vibration and guarantee higher dynamic performance compared to the traditional non-redundant actuation modes. Finally, a virtual prototype model is developed to demonstrate the validity of the presented RFDM. The systematic methodology proposed in this study can be conveniently extended for the dynamic modeling and controller design of other planar flexible parallel manipulators, especially the emerging ones with multiple actuation modes. [ABSTRACT FROM AUTHOR]

• Novel cross-flow heat exchangers (HXs) using bioinspired structures are constructed. • Heat transfer performance and flow characteristics of the metal HXs are analyzed. • Simulation models of the HXs are established and validated. • S-D structure shows enormous potential in constructing high-performance compact HXs. Combining additive manufacturing (AM) and bioinspired structures, this study reports the design, fabrication, flow characteristics and heat transfer performance of three novel cross-flow metal heat exchangers (HXs) based on triply periodic minimal surface (TPMS) topologies. Numerical simulations of the TPMS HXs are also validated using associated experimental results for the first time. Results show that, the helically curved channels in the Schwarz-D (S-D) and Gyroid HXs promote flow mixing and induce large-scale bifurcation flow, while the Primitive HX provides basically a through-flow structure. Owing to the complex three-dimensional flow pattern and significantly increased heat transfer surface, the S-D HX provides 41–52% and 4–12% higher heat transfer rates relative to the Primitive HX and Gyroid HX. In addition, the presence of the baffles at the inlet results in similar pressure drops among the three HXs. Compared with the reference HXs reported in the literature, the current Gyroid and S-D HXs show comparable heat transfer performance with significant advantages in terms of pressure drop penalties. Since the surface-to-volume ratio of the TPMS units increases exponentially with decreasing unit size, it is believed that TPMS HXs employing smaller unit size will greatly enhance their compactness and heat transfer performance. [ABSTRACT FROM AUTHOR]

Background: Cytoplasmic male sterility (CMS) is the basis of heterosis exploitation. CMS has been used to hybrid production in cotton, but its molecular mechanism remains unclear. CMS is associated with advanced or delayed tapetal programmed cell death (PCD), and reactive oxygen species (ROS) may mediate this process. In this study, we obtained Jin A and Yamian A, two CMS lines with different cytoplasmic sources. Results: Compared with maintainer Jin B, Jin A anthers showed advanced tapetal PCD with DNA fragmentation, producing excessive ROS which accumulated around the cell membrane, intercellular space and mitochondrial membrane. The activities of peroxidase (POD) and catalase (CAT) enzymes which can scavenge ROS were significantly decreased. However, Yamian A tapetal PCD was delayed with lower ROS content, and the activities of superoxide dismutase (SOD) and POD were higher than its maintainer. These differences in ROS scavenging enzyme activities may be caused by isoenzyme gene expressions. In addition, we found the excess ROS generated in Jin A mitochondria and ROS overflow from complex III might be the source in parallel with the reduction of ATP content. Conclusion: ROS accumulation or abrogation were mainly caused by the joint action of ROS generation and scavenging enzyme activities transformation, which led to the abnormal progression of tapetal PCD, affected the development of microspores, and eventually contributed to male sterility. In Jin A, tapetal PCD in advance might be caused by mitochondrial ROS overproduction, accompanied by energy deficiency. The above studies will provide new insights into the cotton CMS and guide the follow-up research ideas. [ABSTRACT FROM AUTHOR]

Gastric cancer (GC) has been identified as the third deadly cancer in the world. Accumulating researches suggest a potential role of microorganisms in tumorigenesis. However, the composition of microbiota in GC tissues is not clear and it changes throughout the different stages of GC remain mostly elusive. Our study integrated RNA-Seq data of 727 samples derived from gastric tissues across four datasets and revealed its microbial composition. In order to remove the false positive results, core taxa were defined and characterized. Based on it, we analyzed the influence of biological factors on its composition. The pan-microbiome of gastric tissues was estimated to be over than 1400 genera. Seventeen core genera were identified. Among them, Helicobacter, Lysobacter were significantly enriched in normal tissues, while Pseudomonas was enriched in tumor tissues. Interestingly, Acinetobacter, Pasteurella, Streptomyces, Chlamydia, and Lysobacter, showed a significant increase trend during tumor development and formed strong intra/inter-correlations among them or with other genera. Furthermore, we found that tumor stage played an important role in altering the microbial composition of GC tissues. This study provides support for the in-depth study of tumor microbiome, and the specific microbiome excavated provides a possibility for the subsequent identification of potential biomarkers for GC. [ABSTRACT FROM AUTHOR]

CD8+ exhausted T cells (Tex) are heterogeneous. PD-1 inhibitors reinvigorate progenitor Tex, which subsequently differentiate into irresponsive terminal Tex. The ability to maintain a capacity for durable proliferation of progenitor Tex is important, but the mechanism remains unclear. Here, we showed CD8+ progenitor Tex pretreated with decitabine, a low-dose DNA demethylating agent, had enhanced proliferation and effector function against tumors after anti–PD-1 treatment in vitro. Treatment with decitabine plus anti–PD-1 promoted the activation and expansion of tumor-infiltrated CD8+ progenitor Tex and efficiently suppressed tumor growth in multiple tumor models. Transcriptional and epigenetic profiling of tumor-infiltrated T cells demonstrated that the combination of decitabine plus anti–PD-1 markedly elevated the clonal expansion and cytolytic activity of progenitor Tex compared with anti–PD-1 monotherapy and restrained CD8+ T cell terminal differentiation. Strikingly, decitabine plus anti–PD-1 sustained the expression and activity of the AP-1 transcription factor JunD, which was reduced following PD-1 blockade therapy. Downregulation of JunD repressed T cell proliferation, and activation of JNK/AP-1 signaling in CD8+ T cells enhanced the antitumor capacity of PD-1 inhibitors. Together, epigenetic agents remodel CD8+ progenitor Tex populations and improve responsiveness to anti–PD-1 therapy. [ABSTRACT FROM AUTHOR]

Emerging active distribution systems are operated under more complicated and uncertain conditions. Because of frequent topology changes or temporary malfunctions of data acquisition, the network may lose observability and in turn may lead to the failure of distribution system state estimation. Without distribution system state estimation, the distribution system operator may not be able to make secure decisions, and the system may face with risk of serious damages. In this paper, a new real/reactive (PQ) decoupled 3-phase numerical observability analysis method and a new critical data identification method for distribution systems are proposed. The methods can efficiently identify all unobservable branches and critical data in a non-iterative manner. In addition to the 3-phase decoupling, the normal equation is also PQ decoupled, and the computation burden is greatly reduced. Furthermore, all entries in the Jacobian matrix are non-negative integers and the proposed methods present good numerical performance. Strict theoretical proofs on the performance of the proposed methods are provided and numerical results on different scales of test systems illustrate their validities. [ABSTRACT FROM AUTHOR]

In the paper, a new mass-preserving and modified-upwind S-DDM scheme over non-overlapping multi-block sub-domains for solving time-dependent convection–diffusion equations in two dimensions is developed and analyzed. On each sub-domain, the intermediate fluxes on the interfaces of sub-domains are firstly computed by the modified semi-implicit flux schemes. Then, the solutions and fluxes in the interiors of sub-domains are computed by the modified-upwind splitting implicit solution and flux coupled schemes. On the theoretical aspect, analyzing the mass-preserving and modified-upwind S-DDM scheme is difficult over non-overlapping multi-block sub-domains due to the combination of the splitting technique, the conservative modified-upwind technique, and the domain decomposition. We prove the proposed scheme to be mass conservative and unconditionally stable in discrete L 2 -norm and further prove its convergence and obtain error estimates. Numerical experiments are presented to illustrate mass conservation, convergence and parallelism. [ABSTRACT FROM AUTHOR]

Tetralogy of fallot (TOF) is one of the most prevalent types of congenital heart diseases. As a category of bioactive molecules, peptides have been proved to participate in various biological processes. However, the role of endogenous peptides in the pathogenesis of TOF has not been studied. In this study, we performed a comparative peptidomic profile in the fetal heart of TOF and the control group for the first time by liquid chromatography-tandem mass spectrometry. Our data demonstrated that a total of 201 peptides derived from 176 precursor proteins were differentially expressed in the heart tissues of TOF fetuses compared with normal controls, including 41 upregulated peptides and 160 downregulated peptides. After analyzing the characteristics of these differentially expressed peptides and their precursor proteins, we found that these peptides were potentially involved in different biological processes, especially cardiogenesis and congenital anomaly of the cardiovascular system. Interestingly, we detected several extracellular matrix-derived peptides involved in our differentially expressed peptidomic profile. In summary, our study constructed a comparative peptidomic profile from the heart tissues of TOF fetuses and normal controls, and it identified a series of peptides that could potentially participate in heart development and TOF formation. The emergence of our peptidomics study indicated a new perspective to explore the pathogenesis of abnormal heart morphology, especially TOF. [ABSTRACT FROM AUTHOR]

The influence of SBS and SBR on the properties of cement emulsified asphalt mortar was studied. The results show that the fluidity and air content of mortars decrease with the SBR content, and increase with the SBS content. The type and content of modifiers have significant effect on the later strength of mortars. The toughness of mortars increases with the increase of modifier content, and decreases with the age. After 100 freeze-thaw cycles, the quality and the strength loss of mortars increase, and the strength loss of mortars with SBS is lower than that with SBR. [ABSTRACT FROM AUTHOR]

The prefitting and backfitting methods are commonly used to sparsify the full solution of naive kernel minimum squared error. As known to us, the forward learning methods including prefitting and backfitting only assist us in finding the suboptimal solutions. To enhance the testing real time further, in this paper by virtue of the idea of incorporating the backward learning algorithm into the forward learning algorithm, two improved schemes on the basis of prefitting and backfitting are proposed. Compared with the original versions, two improved algorithms obtain fewer significant nodes, which indicates much better testing real time. Due to the addition of the backward learning to the forward learning, the proposed algorithms need more training computational costs. Investigations on benchmark data sets and a robot arm example are reported to demonstrate the improved effectiveness. [ABSTRACT FROM AUTHOR]

In this article, we study the Drude models of Maxwell's equations in three-dimensional metamaterials. We derive new global energy-tracking identities for the three dimensional electromagnetic problems in the Drude metamaterials, which describe the invariance of global electromagnetic energy in variation forms. We propose the time second-order global energy-tracking splitting FDTD schemes for the Drude model in three dimensions. The significant feature is that the developed schemes are global energy-preserving, unconditionally stable, second-order accurate both in time and space, and computationally efficient. We rigorously prove that the new schemes satisfy these energy-tracking identities in the discrete form and the discrete variation form and are unconditionally stable. We prove that the schemes in metamaterials are second order both in time and space. The superconvergence of the schemes in the discrete H1 norm is further obtained to be second order both in time and space. Their approximations of divergence-free are also analyzed to have second-order accuracy both in time and space. Numerical experiments confirm our theoretical analysis results. © 2017 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 33: 763-785, 2017 [ABSTRACT FROM AUTHOR]

This study evaluated the effects of two types of cationic modified asphalt emulsions, i.e. SBS modified asphalt emulsion and SBR modified asphalt emulsion, on the flow time, air content and mechanical properties of cement emulsified asphalt mortar (CEAM) at varying asphalt to cement (A/C) ratios. The flow time and air content of fresh CEAM were measured, and the compressive strength, elastic modulus and impact toughness of hardened CEAM were tested. The experimental results show that the flow time, air content and toughness increase with the increase of A/C ratio, while the compressive strength and 28d elastic modulus show a different trend. The effects of modifiers on the properties of CEAM are different. The flow time, air content and toughness increase with the SBS content, while the compressive strength and 28d elastic modulus show the opposite trend. Contrary to the toughness, the flow time, air content, compressive strength and 28d elastic modulus decrease with the SBR content. [ABSTRACT FROM AUTHOR]

To elucidate metabolism of ascorbic acid (AsA) in sweet cherry fruit (Prunus avium ‘Hongdeng’), we quantified AsA concentration, cloned sequences involved in AsA metabolism and investigated their mRNA expression levels, and determined the activity levels of selected enzymes during fruit development and maturation. We found that AsA concentration was highest at the petal-fall period (0 days after anthesis) and decreased progressively during ripening, but with a slight increase at maturity. AsA did nevertheless continue to accumulate over time because of the increase in fruit fresh weight. Full-length cDNAs of 10 genes involved in the L-galactose pathway of AsA biosynthesis and 10 involved in recycling were obtained. Gene expression patterns of GDP-L-galactose phosphorylase (GGP2), L-galactono-1, 4-lactone dehydrogenase (GalLDH), ascorbate peroxidase (APX3), ascorbate oxidase (AO2), glutathione reductase (GR1), and dehydroascorbate reductase (DHAR1) were in accordance with the AsA concentration pattern during fruit development, indicating that genes involved in ascorbic acid biosynthesis, degradation, and recycling worked in concert to regulate ascorbic acid accumulation in sweet cherry fruit. [ABSTRACT FROM AUTHOR]

Persistent scatterer interferometry (PS-InSAR) is a common technique used in surface motion estimation. However, it is not easy to fully analyse the results, especially for non-experts. Due to the complexity of the formation of Persistent Scatterers (PS) points as well as the large difference in scale and time-series characteristics, it is necessary to develop new visualization methods for a better understanding and analysis of PS-InSAR data. In this article, we implement a dynamic online visualization for PS-InSAR surface motion estimation results using WebGL. A 3D interactive visualization method gives users vivid experiences with interactive operations so that they can easily observe scene details. Animation is used to show the development of surface motion over time as estimated using PS-InSAR, presenting results in an intuitive way through scientific visualization methods. Online visualization through our application makes PS-InSAR results accessible and relevant to dispersed users from diverse domains. [ABSTRACT FROM AUTHOR]

The gear drive with tubular tooth surfaces having double contact points is proposed. The generation of gear pair is investigated based on two mismatched rack cutters. The basic tooth profiles of rack cutters for generating the pinion and the gear are designed, respectively. Mathematical models of tooth surfaces are derived according to the geometric relationships. Solid models of gear pair are also established. Stress analysis of tubular tooth surfaces having double contact points is carried out using the finite element method. The results show that the proposed gear drive has the better transmission characteristics. Gear prototype is finished with CNC machining technology. The further studies on the dynamic characteristics and experimental test of this gear drive will be carried out. [ABSTRACT FROM AUTHOR]

Highly concentrated viscoelastic paraffin oil-in-water emulsions were prepared by using tetradecyltrimethylammonium laurate (TTAL) as the emulsifier at a water percentage of 10%. The influences of four different inorganic salts, i.e., NaCl, NaBr, CaCl 2 and MgSO 4 , on the structures and rheological properties of the emulsions have been investigated. It was found that the addition of salt eventually induces macroscopic phase separation of the emulsions and the influence following the order of NaCl < NaBr < CaCl 2 < MgSO 4 . At intermediate salt concentrations, the introduction of salt leads to obvious viscoelasticity enhancement of the emulsions. The ability of the salt to induce the viscoelasticity enhancement approximately follows an opposite order to that found in phase separation, which is 100 folds at 500 mmol L −1 NaCl (potentially not reach the maximum), 400 folds at 300 mmol L −1 NaBr, 10 folds at 50 mmol L −1 CaCl 2 and 6 folds at 15 mmol L −1 MgSO 4 , respectively. It is speculated that the adsorption of the inorganic cation and anion onto the charged surfactant monolayer at the oil/water interface changes the properties of the emulsion droplets, accounting for this unusual viscoelasticity enhancement. By conductivity measurements, it is also evidenced that the dissociation and mobility of the adsorbed ions can be hardly influenced by temperature, which leads to pronounced stability of the emulsions at elevated temperatures. The salt-induced structural transitions have been monitored by optical microscopy and confocal fluorescence microscopy observations, both of which show the presence of large oil droplets surrounded by hierarchically-organized smaller ones. [ABSTRACT FROM AUTHOR]

According to the present vehicle-to-grid situation and existing pricing strategy in China, this paper proposed a two-level evolution game model for pricing analysis problem. The model contains two level game models: the up level game operated between monopoly electricity sale enterprise and small electricity sale enterprise; the second level is game between electricity sale enterprise and EV user; a pay-off matrix in ternary nonlinear equation form is built to descries the evolution process under different strategies. After the Linearization of nonlinear equations, the evolution stable strategy (ESS) is deduced for evolution game model. Analysis work is carried out depending on the ESS. Finally, the numerical results are given by computer simulation. Several suggestions of pricing strategies in China’s electricity market are obtained. [ABSTRACT FROM AUTHOR]

Prostaglandin endoperoxide H synthase-2 (PGHS-2), also called cyclooxygenase-2 (COX-2), converts arachidonic acid to PGH2. PGHS-2 is a conformational heterodimer composed of allosteric (Eallo) and catalytic (Ecat) subunits. Fatty acids (FAs) bind to Arg-120 of Eallo increasing to different degrees, depending on the FA, the Vmax of its Ecat partner. We report here that movement of helical residues 120-122 and loop residues 123-129 of Eallo underlies the allosteric effects of FAs and allosteric COX-2 inhibitors, including naproxen and flurbiprofen. An S121P substitution in both PGHS-2 monomers yields a variant (S121P/S121P PGHS-2) that has 1.7-1.8 times the Vmax of native PGHS-2 and is relatively insensitive to activation by FAs or inhibition by allosteric inhibitors. The S121P substitution in Eallo is primarily responsible for these effects. In X-ray crystal structures, the Cα atoms of helical residues 119-122 of S121P/S121P PGHS-2 are displaced from their normal positions. Additionally, the S121P/S121P PGHS-2 variants in which Pro-127 and Ser-541 are replaced by cysteines spontaneously forms Cys-127 to Cys-541 cross-links between monomers. This is unlike the corresponding native PGHS-2 variant and suggests that S121P substitutions also unhinge the loop involving residues 123-129. We conclude the following: (a) the region involving residues 120-129 of unoccupied Eallo tonically inhibits Ecat; (b) binding of an activating FA (e.g. arachidonic, palmitic, or oleic acid) to Eallo or an S121P substitution in Eallo repositions this region to increase Ecat activity; and (c) allosteric COX inhibitors act by preventing FA binding to Eallo and additionally by relocating Eallo residues to inhibit Ecat. [ABSTRACT FROM AUTHOR]

This article describes a Bayesian approach for ensuring the continuity of remote sensing records (1982–2014) by back-prediction of Moderate Resolution Imaging Spectroradiometer (MODIS) using historical Advanced Very High Resolution Radiometer (AVHRR) data. First, a historical 8 km snow data was generated using MODIS snow Quality Assurance field and North American Regional Reanalysis snow depth and air temperature outputs. Second, the relationships between coarsened 8 km MODIS and AVHRR Normalized Difference Vegetation Index (NDVI) were modeled pixel by pixel using spatial autocorrelation. Then the NDVI was back-predicted to 1982 from historical AVHRR observations and snow data. The back-predicted NDVI was validated against those data held-out from MODIS in 2001 and 2002 from four distinct biogeographic state regions (California, Kansas, Minnesota and Mississippi) in the continental United States. The results show consistency of the derived NDVI from two sensors, with a Root Mean Square Error within 0.05 over most land cover classes. This validation results suggest potential application of this approach for generating consistent long term multi-sensor NDVI data records for ecology and global climate change studies. [ABSTRACT FROM AUTHOR]

In this paper, a splitting characteristic method is developed for solving general multi-component aerosol transports in atmosphere, which can efficiently compute the aerosol transports by using large time step sizes. The proposed characteristic finite difference method (C-FDM) can solve the multi-component aerosol distributions in high dimensional domains over large ranges of concentrations and for different aerosol types. The C-FDM is first tested to compute the moving of a Gaussian concentration hump. Comparing with the Runge-Kutta method (RKM), our C-FDM can use very large time step sizes. Using Δ t = 0.1, the accuracy of our C-FDM is 10 −4 , but the RKM only gets the accuracy of 10 −2 using a small Δ t = 0.01 and the accuracy of 10 −3 even using a much smaller Δ t = 0.002. A simulation of sulfate transport in a varying wind field is then carried out by the splitting C-FDM, where the sulfate pollution is numerically showed expanding along the wind direction and the effects of the different time step sizes and different wind speeds are analyzed. Further, a realistic multi-component aerosol transport over an area in northeastern United States is studied. Concentrations of PM 2.5 sulfate, ammonium, nitrate are high in the urban area, and low in the marine area, while sea salts of sodium and chloride mainly exist in the marine area. The normalized mean bias and the normalized mean error of the predicted PM 2.5 concentrations are −6.5% and 24.1% compared to the observed data measured at monitor stations. The time series of numerical aerosol concentration distribution show that the strong winds can move the aerosol concentration peaks horizontally for a long distance, such as from the urban area to the rural area and from the marine area to the urban and rural area. Moreover, we also show the numerical time duration patterns of the aerosol concentration distributions due to the affections of the turbulence and the deposition removal. The developed splitting C-FDM algorithm can be applied to model spatial multi-component aerosol transport problems in large domains in atmosphere. [ABSTRACT FROM AUTHOR]

Atrial natriuretic peptide (ANP)-mediated natriuretic response is a well-established cardiac endocrine function. Corin is a transmembrane protease that activates ANP in the heart. Corin expression has been detected in non-cardiac tissues including the kidney. Here we examined corin, pro-ANP/ANP and natriuretic peptide receptor-A (NPR-A) expression in human renal segments. By immunostaining and in situ hybridization, we found similar corin, pro-ANP/ANP and NPR-A protein and mRNA expression in human renal segments. The expression was most abundant in the proximal convoluted tubules and the medullary connecting ducts. In the proximal tubules, corin protein was present in the apical membrane region underneath the brush border where the ANP-degrading protease neprilysin was abundant. These results suggest that corin-mediated pro-ANP activation may occur in renal segments and that locally produced ANP may act in an autocrine manner to regulate sodium and water reabsorption in situ. Our results also point to the proximal convoluted tubules as a major site for local ANP action. Such a renal corin/ANP autocrine mechanism may differ from the cardiac corin/ANP endocrine mechanism in regulating sodium homoeostasis under physiological and pathological conditions. [ABSTRACT FROM AUTHOR]

In order to evaluate the shearing quality, the material inhomogeneity through thickness after shearing is introduced by the authors. This study investigates the shearing and local formability of hot-rolled high-strength steel (HSS) plate, which is generally exploited for the manufacturing of the beam of heavy trucks. Various kinds of plates with different thicknesses and strengths are used to figure out the effect of material properties on the shearing quality. Both the shear surface morphology and microhardness distribution of the sheared edge are considered for evaluating the influence of the sheared-edge quality on local formability during the following forming process. Vickers hardness tests are conducted to analyze the microhardness distribution on the shear surface, which is proved to have significant effect on the local formability of the sheared edge. Furthermore, two kinds of bending tests and simulation are employed to study the edge cracking phenomenon, and the results indicate that the junctional zone of burnished zone and fracture zone, which is defined as peak hardness zone (PHZ), has a significant impact on major strain distribution on shear surface in the side bending test and this region is the main cause of edge cracking in normal bending test. [ABSTRACT FROM AUTHOR]

CD36, a scavenger receptor, plays an important role in the progression of atherosclerosis through its interaction with oxidized low-density lipoprotein (ox-LDL). Porphyromonas gingivalis ( P. gingivalis , Pg ) has been shown to promote macrophage-derived foam cell formation by affecting the expression of CD36. However, the regulatory role of CD36 in macrophages infected with Pg remains largely unknown. Therefore, the aim of the present study was to explore the molecular mechanism of Pg induced CD36 expression in macrophages. Our results showed that Pg promoted ox-LDL uptake by macrophages and the formation of foam cells. Pg infection increased CD36 mRNA and protein levels in ox-LDL-untreated macrophages. Moreover, small interferon RNA (siRNA) targeting CD36 significantly reduced foam cell formation induced by Pg . Additionally, Pg stimulated nuclear translocation of p65, which directly bound to the promoters of CD36 to facilitate its transcription. Inhibition of p65, NF-κB or ERK1/2 blocked Pg -induced CD36 production; whereas, overexpression of NF-κB subunits p65 and p50 upregulated CD36. Furthermore, Ras inhibitors significantly attenuated ERK1/2 activation and CD36 expression. Taken together, the data indicated that stimulation of the ERK/NF-κB pathway by Pg led to transactivation of the CD36 promoters, thereby upregulating CD36 expression in the infected macrophages. These findings may help design new treatment strategies in atherosclerosis. [ABSTRACT FROM AUTHOR]

Mn 3 B 7 O 13 Cl nanocrystals were firstly prepared by sol-gel process. X-ray diffraction (XRD) and transmission electron microscope (TEM) were utilized to characterize the structure, shape, size of the obtained products. Microstructure and luminescence characteristics of Mn 3 B 7 O 13 Cl were discussed. The results show that Mn 3 B 7 O 13 Cl nanocrystals can be obtained after xerogel was roasted at 550 °C, the nanocrystals are uniform and the average crystal size is about 50 nm. Two luminescence channels can be observed in Mn 3 B 7 O 13 Cl nanocrystal. Luminescence around green wave band (511–541 nm) and red wave band (686–731 nm) are the emission of Mn 2+ which occupies the center of tetragonal coordination and octahedral coordination, respectively. Both of them are assigned to the transition from 4 T 1 (G) to 6 A 1 (S) of Mn 2+ . [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors, which is causing the second leading cancer-related death worldwide. With the significant advances of high-throughput protein analysis techniques, the proteomics offered an extremely useful and versatile analytical platform for biomedical researches. In recent years, different proteomic strategies have been widely applied in the various aspects of HCC studies, ranging from screening the early diagnostic and prognostic biomarkers to in-depth investigating the underlying molecular mechanisms. In this review, we would like to systematically summarize the current applications of proteomics in hepatocellular carcinoma study, and discuss the challenges of applying proteomics in study clinical samples, as well as discuss the possible application of proteomics in precision medicine. Biological significance In this review, we have systematically summarized the current applications of proteomics in hepatocellular carcinoma study, ranging from screening biomarkers to in-depth investigating the underlying molecular mechanisms. In addition, we have discussed the challenges of applying proteomics in study clinical samples, as well as the possible applications of proteomics in precision medicine. We believe that this review would help readers to be better familiar with the recent progresses of clinical proteomics, especially in the field of hepatocellular carcinoma research. [ABSTRACT FROM AUTHOR]

Dielectric metasurfaces built up with nanostructures of high refractive index represent a powerful platform for highly efficient flat optical devices due to their easy-tuning electromagnetic scattering properties and relatively high transmission efficiencies. Here we show visible-frequency silicon metasurfaces formed by three kinds of nanoblocks multiplexed in a subwavelength unit to constitute a metamolecule, which are capable of wavefront manipulation for red, green, and blue light simultaneously. Full phase control is achieved for each wavelength by independently changing the in-plane orientations of the corresponding nanoblocks to induce the required geometric phases. Achromatic and highly dispersive meta-holograms are fabricated to demonstrate the wavefront manipulation with high resolution. This technique could be viable for various practical holographic applications and flat achromatic devices. [ABSTRACT FROM AUTHOR]

The flow-induced interior noise in pump as turbine (PAT) consists of flow-borne noise and flow-induced structure noise from dipole source. Without accurate distinguishing of main interior noise, the noise control and management cannot be guided. The experiments of flow-induced interior noise and free modals for rotor and casing were performed to validate the accuracy of numerical methods. The computational models for flow-induced noise and flow-borne noise considering structure in interior acoustic field were developed. On the basis of this, the spectrum characteristics of each noise source and their contribution to the total noise were distinguished. It is found that within interior noise, the radiated energy of flow-induced structure noise is less than that of flow-borne noise generated by dipole source. Compared with the experiment, the flow-borne noise considering structure due to casing source can more precisely reflect joint action of multiple sources. Especially in larger flow conditions, the maximum error is only 5.9% at Blade-Passing Frequency (BPF) and its harmonics. [ABSTRACT FROM AUTHOR]

The increasing of distributed generators and high demand of customer service quality of recent years keep challenging the design and operation of electric power distribution systems. The future smart distribution grid is envisioned to be a large complex cyber‐physical distribution system (CPDS), where physical grid components are monitored and controlled based on the interactions on the cyber space. As sensors and controllers, smart feeder remote terminal units (FRTUs) transfer necessary data to the control centre for situational awareness, and receive orders from the control centre for dynamic controlling. This study introduces an analytical FRTU deployment approach for the reliability improvement of integrated CPDSs. The FRTU deployment problem is modelled as a mixed‐integer non‐linear programming problem, which aims to minimise the total cost with the reliability index of average service available index as the constraint. Two kinds of distribution feeders (overhead and underground) are considered. The total cost includes the life cycle cost of FRTUs in addition to customer interruption cost. The proposed model can be solved by large‐scale commercial solvers in an efficient manner. Test results of the RBTS‐BUS4 distribution system and a China Southern Power Grid 62‐bus distribution system validate the accuracy and effectiveness of the approach. Comparison with the genetic algorithm also shows its great efficiency. [ABSTRACT FROM AUTHOR]

Biomass and fishmeal are two typical organic substances which would self-heat during transport and storage. This paper, we studied the self-heating and spontaneous combustion risk of biomass and fishmeal with thermal analysis (DSC-TG) and self-heating substances test experiments. From DSC-TG of biomass and fishmeal, the heat flow (exotherm) of main decomposition stage for biomass was far higher than that of fishmeal (over twice) and the mass of biomass decreased more quickly during this process. From the self-heating substances test experiments, our biomass sample is not a self-heating substance while our fishmeal sample has low risk of self-heating and spontaneous combustion if it was transported in packages of not more than 3 cubic metres volume according to the classification of self-heating substances. Moreover, activation energy of biomass and fishmeal are calculated based on the kinetics of thermal analysis. Then, CATs of biomass and fishmeal were calculated based on Frank-Kamenetskii theory. The calculated CATs of 1.6 m cube (whose volume is over 3 cubic metres) for biomass and fishmeal are 107.8 °C and 86.7 °C respectively. Though there is still higher risk of self-heating and spontaneous combustion for fishmeal than biomass, there is still relatively low risk of self-heating and spontaneous combustion for both fishmeal and biomass when the volume is around 3 cubic metres. [ABSTRACT FROM AUTHOR]