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In this work, we employed an asymmetric auxiliary organic ligand (1,1,1-trifluoroacetylacetone, Htfac) to further regulate the magnetic relaxation behavior of series of Dy

Orange juice is a kind of fruit juice with huge market share. The most common adulteration is the addition of mandarin juice and grapefruit juice. Therefore, it is necessary to develop a method that can simultaneously detect mandarin and grapefruit components in orange juice. In this study, the specific site of the trnL-trnF gene of mandarin and the specific site of the accD-psaI gene of grapefruit were used for digestion and capillary electrophoresis separation to establish a duplex PCR–RFLP–CE method of simultaneous detection of mandarin and grapefruit components. By this method, the detection limits of mandarin and grapefruit components were 5% and 2.5%, respectively. About the specificity, only the 83–177 bp amplified bands of mandarin and grapefruit were specifically digested, while none of them were cut in the 8 kinds of fruits such as pear, apple, peach, papaya, pineapple, hawthorn, grape and banana. Duplex PCR–RFLP–CE tests were performed on the 8 commercially available fruit juices. As a result, grapefruit components were found in orange juice (C5) and other ingredients to be identified in grapefruit juice (C8). The established duplex PCR–RFLP–CE method can provide an effective detection method for orange juice adulteration in the future.

In order to select plant materials suitable for the ecological restoration of abandoned mining land, ecological restoration experiments were set up in landfills. The effects of different ecological restoration measures on plant diversity and heavy metal enrichment and migration characteristics were studied. The results showed that under different ecological restoration measures, a total of eight families and 10 species of surviving plants appeared, most of which were herbs. The restoration effect of the arbor shrub and grass plots was the best; the plant coverage reached 100%, and the survival rate was over 69%. The diversity index of the plant community was as follows:arbor shrub grassshrub grassjoe grassgrass. The dominant plants under different ecological restoration measures were

The hybridizations of machine learning and quantum physics have caused essential impacts to the methodology in both fields. Inspired by quantum potential neural network, we here propose to solve the potential in the Schrödinger equation provided the eigenstate, by combining Metropolis sampling with deep neural network, which we dub as Metropolis potential neural network (MPNN). A loss function is proposed to explicitly involve the energy in the optimization for its accurate evaluation. Benchmarking on the harmonic oscillator and hydrogen atom, MPNN shows excellent accuracy and stability on predicting not just the potential to satisfy the Schrödinger equation, but also the eigen-energy. Our proposal could be potentially applied to the ab-initio simulations, and to inversely solving other partial differential equations in physics and beyond.

Constructing quantum circuits for efficient state preparation belongs to the central topics in the field of quantum information and computation. As the number of qubits grows fast, methods to derive large-scale quantum circuits are strongly desired. In this work, we propose the automatically differentiable quantum circuit (ADQC) approach to efficiently prepare arbitrary quantum many-qubit states. A key ingredient is to introduce the latent gates whose decompositions give the unitary gates that form the quantum circuit. The circuit is optimized by updating the latent gates using back propagation to minimize the distance between the evolved and target states. Taking the ground states of quantum lattice models and random matrix product states as examples, with the number of qubits where processing the full coefficients is unlikely, ADQC obtains high fidelities with small numbers of layers $N_L \sim O(1)$. Superior accuracy is reached compared with the existing state-preparation approach based on the matrix product disentangler. The parameter complexity of MPS can be significantly reduced by ADQC with the compression ratio $r \sim O(10^{-3})$. Our work sheds light on the "intelligent construction" of quantum circuits for many-qubit systems by combining with the machine learning methods., Comment: 5 pages, 5 figures

State preparation is of fundamental importance in quantum physics, which can be realized by constructing the quantum circuit as a unitary that transforms the initial state to the target, or implementing a quantum control protocol to evolve to the target state with a designed Hamiltonian. In this article, we study the latter on quantum many-body systems by time evolution with fixed couplings and variational magnetic fields. Specifically, we consider preparing the ground states of the Hamiltonians containing certain interactions that are missing in the Hamiltonians for the time evolution. An optimization method is proposed to optimize the magnetic fields by ``fine graining'' the discretization of time, in order to gain high precision and stability. The automatic differentiation technique is utilized to obtain the gradients of the fields against the logarithmic fidelity. Our method is tested on preparing the ground state of the Heisenberg chain with the time evolution by the $XY$ and Ising interactions, and its performance surpasses two baseline methods that use local and global optimization strategies, respectively. Our work can be applied and generalized to other quantum models such as those defined on higher-dimensional lattices. It enlightens to reduce the complexity of the required interactions for implementing quantum control or other tasks in quantum information and computation by means of optimizing the magnetic fields.

The incorporation of unsaturated [Mn(1,2-dap)]2+, [Mn(1,2-dap)2]2+, [Mn(2,2-bipy)]2+ (1,2-dap=1,2-diaminopropane) complex cations with thioarsenate anions of [AsIIIS3]3− and [AsVS4]3− led to three new hybrid manganese thioarsenates, namely, [Mn(1,2-dap)]2MnAs2S6 (1), [Mn(1,2-dap)2]{[Mn(1,2-dap)]2As2S8} (2) and (NH4)[Mn(2,2-bipy)2]AsS4 (3). In compound 1, the unsaturated [Mn(1,2-dap)]2+ complexes, [MnS4]6− tetrahedra and [AsIIIS3]3− trigonal-pyramids are condensed to form the 1D [Mn(1,2-dap)]2MnAs2S6 chain, whereas compound 2 features 2D layer composed of [Mn(1,2-dap)]2+ and [Mn(1,2-dap)2]2+ complexes as well as [AsVS4]3− tetrahedral units. For compound 3, two [AsVS4]3− anions bridge two [Mn(2,2-bipy)]2+ complex cations into a butterfly like {[Mn(2,2-bipy)]2As2S8}2− anionic unit. Magnetic measurements indicate the ferrimagnetic behavior for compound 1 and antiferromagnetic (AF) behaviors for compounds 2–3. The UV–vis diffuse-reflectance measurements and electronic structural calculations based on density functional theory (DFT) revealed the title compounds belong to semiconductors with band gaps of 2.63, 2.21, and 1.97 eV, respectively. The narrow band-gap of compound 3 led to the efficient and stable photocatalytic degradation activity over organic pollutant than N-doped P25 under visible light irradiation.

A high piezoelectricity enhancement achieved in (Ba,Ca)(Ti,Sn)O 3 lead-free ceramics sintered with 4 mol% Li 2 O additives by intensifying effect of sintering temperature ( T S ) in a wide interval (1300–1450 °C) has been found to be related to both the point defects and phase structures. X-ray photoelectron spectroscopy confirmed a reduction of tetravalent cations in B-sites to lower valence state such as Ti 3+ and Sn 2+ along with an increased content as raising T S . Photoluminescence spectra indicated higher oxygen vacancy concentrations as T S is too low or too high than those at an intermediate T S range, which is attributed to the volatilization of Li + and the inadequate oxygen supply in environment at high T S . Owing to coexisting rhombohedral and tetragonal phases at room temperature, a high piezoelectric coefficient d 33 up to 578 pC/N was achieved as T S =1350 °C.

Purpose Insufficient bone volume compromises the success rate and osseointegration of immediate implantation. The objective of the present study was to engineer bone tissue by using adipose-derived stem cell (ASC) sheets and autologous platelet-rich fibrin (PRF) to enhance new bone formation and osseointegration around dental implants. Material and Methods The proliferation and osteogenic potential of ASCs treated with autologous PRF were evaluated with CCK-8 assays, alkaline phosphatase staining, and real-time quantitative polymerase chain reaction. A 3-wall bone defect around each immediate implant was generated in the mandible and randomly treated with ASC sheets plus PRF (group A), ASC sheets only (group B), PRF only (group C), or no treatment (group D). Micro-computed tomography, biomechanical tests, fluorescent bone labeling, and histologic assessments were performed to evaluate bone regeneration capacity. Results The proliferation and osteogenic potential of canine ASCs were markedly enhanced by PRF. Group A exhibited considerably more new bone formation and re-osseointegration (41.17 ± 1.44 and 55.06 ± 0.06%, respectively) than did the other 3 groups. Fluorescent labeling showed that the most rapid bone remodeling activity occurred in group A (P Conclusion These results suggest that sheets of ASC combined with autologous PRF could be a promising tissue-engineering strategy for bone formation in immediate implantation.

This paper presents the study of the microstructure, element distribution, and phase composition of the NiCr-Cr3C2 coating with the help of an X-ray spectrometer (EDS), X-ray diffractometer (XRD), MH-5LD microhardness tester, XMTD-7000 pin friction and wear tester, and CHI604C electrochemical analyzer. The wear resistance of the layer was analyzed. The results show that the strength of the adhesive NiCr coating layer annealed at 500 °C is higher than that of the non-adhesive layer due to the elimination of the residual stress. Due to the presence of a large amount of the hard ceramic phase of Cr3C2 in the coating, the melting point becomes high, resulting in a higher hardness of the entire NiCr-Cr3C2 coating. The adhesive layer NiCr is characterized with a more stable coefficient of friction after 500 °C annealing due to elimination of the residual stress within the coating. Combined with a higher strength, it suggests better wear resistance. According to the electrochemical test, the coating annealed at 500 °C tends to be less aggressive and exhibits better corrosion resistance.

In this study, a series of (Ba0.95Ca0.05)(Ti0.90Sn0.10)O3–xLiF (BCTS–xLiF) (0≤x≤6 mol%) lead-free piezoceramics were fabricated by a conventional solid-state reaction method. The incorporation of LiF could significantly improve the sinterability of BCTS ceramics by reducing the sintering temperature from 1480 °C to 1250 °C, where a relative density over 90% was achieved with grown grains of 5–20 μm. X-ray diffraction and Raman spectroscopy experiments revealed that BCTS–xLiF ceramics are composed of coexisting R–O–T phases at 0≤x≤1 and R–T phases at 2≤x≤6 at room temperature. Optimal piezoelectric properties of d33=510 pC/N, kp=40.9%, er=5370, tan δ=0.019 and dS/dE=961 pm/V were obtained at x=5, which is attributed to the coexistence of R and T phases with an optimum ratio at room temperature and dense structure with large grains.

This work investigated the enhanced sintering and electrical properties of (Ba 0.95 Ca 0.05 )(Ti 0.90 Sn 0.10 )O 3 - x Li 2 O (BCTSLi x , x = 0, 1, 2, 3, 4, 5 and 6 mol%) lead-free piezoelectric ceramics benefiting from the Li 2 O addition. Highly dense BCTS ceramics with good piezoelectric properties were fabricated at reduced sintering temperatures by adding a small amount of Li 2 O. It was found that the sintering densification is promoted mainly by reaction liquid phase at the early sintering stage and the formation of oxygen vacancies should be considered as an additional factor. The coexistence of R and T phases was confirmed by the Raman spectrum at a temperature range from−50 °C to 40 °C as x = 2 and at room temperature for all other Li 2 O added samples, while their specific ratio of R to T phase decreases with increasing Li 2 O addition. Better properties with d 33 = 457 pC/N, k p = 25.18% and Q m = 491 were obtained when adding 4 mol% Li 2 O, which are attributed dominantly to the appropriate specific ratio of R to T phase because of the similar grain size and density for samples at 3 ≤ x ≤ 6.

Background. Pigment epithelium-derived factor (PEDF) is demonstrated to be elevated in diabetes patients. However, no reports have emerged in pregnant women with gestational diabetes mellitus (GDM). This study was undertaken to investigate serum PEDF levels in GDM women and to evaluate PEDF as a biomarker to predict diabetes postpartum.Methods. Serum PEDF concentration and clinical characteristics were detected in the pregnant women with GDM (n = 120) and without GDM (control group,n = 120).Results. PEDF levels were elevated in subjects with GDM versus controls. Univariate correlations showed that serum PEDF levels were positively correlated with fasting glucose and fasting insulin levels, respectively, and negatively correlated with adiponectin. Receiver operating characteristic (ROC) analysis demonstrated that the AUC of serum PEDF for diabetes mellitus in women postpartum was 0.893.Conclusion. Serum PEDF was elevated in pregnant women with GDM, which is probably an early detection marker for predicting development of GDM to diabetes mellitus.

Microbial density is an important biochemical parameters of the training process. This article adopts the method of online measuring optical density of the reactor to obtain information on the growth of microorganisms, and flow photoelectric colorimetric instrument was developed based on this principles. Through MCU STM32F107VC output PWM to control peristaltic pump, to achieve the culture of continuous flow through the optical flow cuvette, using photocell to detect culture absorbed light intensity. The instrument can display detected parameters independently and adjust the control parameters, also can communicate with the PC by RS485. The instrument can achieve real-time monitoring of the growth of microorganisms in the reactor.

In order to detect Volatile Organic Compounds (VOC) quickly and accurately, a portable electronic nose system was developed which including signal acquisition module, valve control module, embedded modules. Three sensors were used to measure methane, ethanol and formaldehyde gas. We used a three-way valve to control two kinds of gas, in order to avoid the system noise the zero reference was subtracted with the gas being tested. The system could quickly detect the three kinds VOC. The system can play a positive role in the rapid assessment of pollution in industrial parks.

A series of Li2CO3-added (Ba0.95Ca0.05)(Ti0.90Sn0.10)O3 (BCTS) ceramics were prepared by normal sintering at a low temperature of 1300°C; Their microstructure and electrical property evaluation were investigated with special emphases on the effect of Li2CO3 addition. Adding Li2CO3 significantly improves the sinterability of BCTS ceramics, resulting in a reduced sintering temperature by more than 150°C. The coexistence of R and T phases is confirmed by the Raman spectrum at room temperature for all samples and at a temperature range from −80°C to 40°C for sample with 3% mol Li2CO3 addition. The specific ratio of R to T phase decreases with increasing temperature or Li2CO3 addition. A higher er is observed in T phase compared to R phase in the studied BCTS system. Better properties with d33 = 485 pC/N, kp = 39%, and Qm = 191 were obtained for BCTS sample with 3% mol Li2CO3 addition, which is attributed to the increased grain size and density along with the variation in the specific ratio of R to T phase.

High-speed railway passenger train operation plan is an important basis to ensure the quality of transportation services. With construction and development of the country's high-speed railway, design and evaluation of railway passenger train plan theory need to be improved and perfected. On the basis of reading and studying a large amount of the references, this paper summarizes the domestic and overseas high-speed running railway operation modes, the high speed railway train operation programs design and other aspects. Besides, according to the related problems and shortcomings, this paper illustrates the meanings and necessities of analyzing the high-speed railway passenger train program.

The development of high-speed railway has been very fast, while there are still existing many problems to be further studied and discussed, especially the design of high-speed railway Train stops program. The research of classification of high-speed passenger railway nodes has a vital significance for forecast of high-speed railway passenger flow, passenger train operation plan, evaluation and optimization and so on, especially for highspeed railway stopping schedule .This paper analyzes the significance and methods of high-speed passenger railway nodes classification, and designs high-speed rail train line stops program based on the classification. Finally, analyzing the case on the basis of Beijing-Guangzhou high-speed railway, a train stops program will be made bases on the classification of Beijing-Guangzhou high-speed railway passenger transport nodes to verify the feasibility of this study.

This paper gives a review on the study of related factors of non-point source pollution (NPS) in water cycle. Hydrological process features, underlying surface conditions, human activities are sorted to introduce the recent research on NPS progress. Several major factors are divided in each item with developing process. The NPS models in world are introduced as well. Additionally, control approaches for NPS and their effects are summarized. Furthermore, the potential trends of NPS study are discussed.

The total syntheses of norartocarpin and artocarpin, two biologically interesting natural flavonoids with two regioisomeric isoprenyl side chains, were achieved for the first time via a linear reaction sequence of 9 and 12 steps with the overall yields of 14% and 3.5%, respectively, starting from commercially available 1,3,5-trimethoxybenzene.

The polymorphic phase transition (PPT) from tetragonal to orthorhombic symmetry was tailored in lead-free piezoelectric ceramics Li 0.08 (Na 0.52+ x K 0.48 ) 0.92 NbO 3 (LN 0.52+ x KN) by controlling excess Na content, which is opposite to the usually reported orthorhombic–tetragonal phase transition. The grain growth was accelerated by adding excess Na, resulting in an increased grain size from 2–3 μm to 7–8 μm and a bimodal grain size distribution for samples x =0.015–0.04. The optimized piezoelectric properties with, i.e. d 33 =226 pC/N and k p =36.8% were obtained in sample x =0.04 due to the PPT effect. The corresponding T C , P r , and E r were 468 °C, 25.5 μC/cm 2 and 1.20 kV/mm, respectively.

In this work, enlightened by the preparation of the Tokuyama BP-1 bipolar membrane, a modified coating method is attempted to prepare the mono-valent perm-selective cation exchange membrane (CEM). That is, a surface-roughening step is introduced into conventional coating technology to increase the contacting area and strengthen the interaction between modification layer and base membrane. Furthermore, a post-quaternization is carried out after the formation of the cross-linked chitosan layer to weaken the effect of the electrostatic repulsion among the cationic charged macromolecules on the compactness of the modification layer. The SEM images and the diffusion experiments of solute confirm the formation of a dense and smooth cationic modification layer. The electrodialysis experiments of the CEMs corresponding to different preparing stages with respect to H+/Zn2+ system and Na+/Mg2+ system show that the mono-valent perm-selectivity can be endowed successfully to the ordinary CEM. For example, th...

Green degree evaluation is one of the key problems to Green Construction Supply Chain (GCSC) Management. The influential factors of GCSC green degree can be analyzed from resource saving, pollution reduction and economic aspects. And the basic evaluative indexes of GCSC are discussed. Then, a GCSC evaluation model is proposed based on Data Envelopment Analysis (DEA). The application case shows the feasibility of the method for GCSC evaluation.

The new plate heat exchanger with modular design is easy to realize the large-scale. It also has the performance advantage of low pressure drop and anticorrosion. The oil refining, chemical industry, steel and iron, metallurgy, electric power industries will be the future main application of it. According to FLUENT soft, this paper constructs the simulation model of the flat type air heat exchanger reverse-flow unit and cross-flow unit. And it also simulates the actual working conditions for the two units based on the existing data. Then we can get the interrelation of temperature field, stress field and velocity field during the using progress. So it can provide some evidences for analyzing heat transfer and resistance properties of the flat type air heat exchanger

The new plate heat exchanger with modular design is easy to realize the large-scale. It also has the performance advantage of low pressure drop and anticorrosion. The oil refining, chemical industry, steel and iron, metallurgy, electric power industries will be the future main application of it. But the designed engine for product is too big, the production cost is high, the production time is long, and it does not suit for processing experiment. Based on the above product structure and similarity theory, the paper designs another small type of reflux plate heat exchanger and the corresponding bench for testing.

Postnatal mesenchymal stem cells have the capacity to differentiate into multiple cell lineages. This study explored the possibility of dental pulp stem cells (DPSCs) for potential application in tendon tissue engineering. The expression of tendon-related markers such as scleraxis, tenascin-C, tenomodulin, eye absent homologue 2, collagens I and VI was detected in dental pulp tissue. Interestingly, under mechanical stimulation, these tendon-related markers were significantly enhanced when DPSCs were seeded in aligned polyglycolic acid (PGA) fibre scaffolds. Furthermore, mature tendon-like tissue was formed after transplantation of DPSC-PGA constructs under mechanical loading conditions in a mouse model. This study demonstrates that DPSCs could be a potential stem cell source for tissue engineering of tendon-like tissue.

(Ba1−xCax)(Ti0.92Sn0.08)O3 (x = 0.00–0.06 mol) ceramics with a high relative density over 96% were prepared by a conventional sintering method at 1480°C. At room temperature, a polymorphic phase transition from orthorhombic phase to tetragonal phase was confirmed by the XRD patterns in the composition range of 0.04 ≤ x ≤ 0.06. A high piezoelectric coefficient d33 up to 568 pC/N was obtained at x = 0.05 mol, which is higher than the other component of (Ba,Ca)(Ti,Sn)O3 system. At the same time, the corresponding planar electromechanical coupling factor kp, converse piezoelectric coefficient dS/dE, and dielectric constant er reach 47.7%, 1013 pm/V, and 23000, respectively. These results indicate that the (Ba,Ca)(Ti,Sn)O3 ceramics are a promising candidate to replace for the lead-based piezoelectric materials.

A fuzzy optimization model of storage space allocation is proposed, and a rolling-planning method is derived. The model takes the uncertainty of departure time of import containers and arrival time of export containers into account. For each planning horizon, the problem is decomposed into two levels: the first level minimizes the unbalanced workloads among blocks using hybrid intelligence algorithm; based on block workloads allocated in the above level, the second level minimizes the number of blocks to which the same group of import containers are split. Numerical results show that the model reduces workload imbalance, and speeds up the vessel loading and discharging process.

Effective berth and quay-crane allocation improves service level of container terminal. For an efficient assignment, stochastic characteristic of containership arrival time and handling time is a key factor. A berth & quay-crane allocation model under stochastic environments is proposed in this article, so as to minimize the average waiting time of containership in terminal. However, it is solved in polynomial CPU time. So to obtain a good solution with considerably small computational effort, a genetic algorithm is developed with a reduced search set on its property. Numerical experiments show that the proposed model is capable of efficiently and dynamically allocating berths and quay-cranes to calling containerships in real stochastic environments and reflects the risk preference of decision-maker. And the solutions of GA are stable and satisfactory in acceptable CPU time.

Li, Ta and Sb co-doped (Na,K)NbO3 ceramics have been widely investigated due to the significantly enhanced piezoelectric properties attributed to the polymorphic phase transition (PPT). An empirical discriminant k = x/0.3 + y/0.3 + z/0.06 to estimate the PPT composition of Liz(Na0.5+δK0.5−δ)1−zNb1−x−yTaxSbyO3 ceramics was deduced based on a displayed phase diagram between the phase structure and doping contents. The phase structure could be conveniently estimated by k, in which a PPT appeared in the vicinity of k = 1, crossing O symmetry at k 1. Around k = 1, a series of LizNa0.52K0.48−zNb0.90Ta0.05Sb0.05O3 ceramics was prepared by a traditional solid-state reaction in a narrow range 0.03 ≤ z ≤ 0.05. A PPT at room temperature appeared critically in the z = 0.04 composition, indicating a good feasibility of the suggested empirical equation to determine the critical PPT composition in the present study. The optimized piezoelectric properties d33 255 pC N−1 and kp 35.0% were attained due to the PPT behaviour.

Ultrahigh piezoelectric constant (d33 = 683 pC/N) and converse piezoelectric coefficient (dS/dE = 1257 pm/V) were observed in CuO-doped lead-free (Ba,Ca)(Ti,Sn)O3 ceramics at an optimal composition fabricated by a conventional sintering method at a low temperature 1250 °C. Since all samples showed a pure perovskite structure with coexisting multiphases including cubic, tetragonal, orthorhombic, and rhombohedral phases around two converged triple points, a good compositional stability of high piezoelectricity along with a high d33 and dS/dE over 600 pC/N and 1000 pm/V was achieved within a wide compositional region (1.0 ≤ x ≤ 3.0) regardless of the CuO content (x).

The phase structure in the (Ba,Ca)(Ti1−xSnx)O3 lead-free ceramics was evolved from inceptive orthorhombic (O) at 0 ≤ x ≤ 0.04 to a two-phase coexistence of pseudocubic-orthorhombic (PC-O) at 0.06 ≤ x ≤ 0.10 and further to a multiphase coexistence of rhombohedral-pseudocubic-orthorhombic (R-PC-O) at x = 0.11. Due to the multiphase coexistence of R-PC-O at room temperature proved by X-ray diffraction, dielectric constant er and differential scanning calorimetry, an ultrahigh piezoelectric coefficient d33 = 670 pC/N and electrostrain 0.061% were achieved. The high d33 over 520 pC/N was stabilized in a wide compositional range of 0.07 ≤ x ≤ 0.11, suggesting that (Ba,Ca)(Ti,Sn)O3 ceramics are a promising candidate for the lead-free piezoelectric ceramics.

Cubic boron nitride (c-BN) films have been prepared by ionized deposition from evaporated boron and nitrogen gas at a pressure of 10-1 Pa. The film structures were examined by transmission electron microscopy and electeon diffraction. It was found that the structure of BN films could be classified into the following types : amorphous, hexagonal, cubic, and their mixtures. The average grain size of c-BN films was estimated to be less than few thousand angstroms. These structures and grain sizes depended mainly on the deposition conditions such as substrate potential, temperature, and ion current density.