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The vehicle-mounted cold storage plate is an important part of a refrigerated vehicle. Charging time reduction of the cold storage plate has an important role in improving the efficiency of cold chain logistics. A heat pipe integrated cold storage plate was proposed, and the cooling and freezing processes of the cold storage plate were simulated and studied. The reliability of the theoretical model was verified through experiments. The influences of the heat pipe diameter, pipe spacing, refrigerant flow rate in the channel, and Reynolds number on the cooling performance of the cold storage plate were studied using the orthogonal experimental method. Under the condition of a conventional cold storage plate with a single-layer thickness of approximately 50 mm, a pipe diameter of 7 mm, pipe spacing of 39 mm, refrigerant flow rate of 1.2 m/s in the channel, and Reynolds number of 3.89 (optimal parameter), the average freezing time and complete freezing time are 45 min and 78 min, respectively. Compared to the results reported in the literature, the cooling time of the heat pipe integrated cold storage plate under the optimal parameters is significantly reduced.

Objective To explore the predictive value of intraoperative flat CT scan for intracranial hemorrhage after mechanical thrombectomy in patients with acute anterior circulation large vessel occlusion (AAC⁃LVO). Methods A total of 106 patients with AAC⁃LVO who underwent mechanical thrombectomy at The Second Affiliated Hospital of Bengbu Medical University was conducted from March 2020 to June 2023. Intraoperative flat CT scan was performed among above patients to record CT values, high⁃density sign and mass effect. According to whether occurred intracranial hemorrhage after surgery, those patients were divided into intracranial hemorrhage group (n = 29) and non⁃intracranial hemorrhage group (n = 77). Univariate and multivariate stepwise Logistic regression analyses were used to screen the influencing factors of intracranial hemorrhage after mechanical thrombectomy. Receiver operating characteristic (ROC) curve was drawn to evaluate the predictive efficacy of intraoperative flat CT scan for postoperative intracranial hemorrhage. Results Logistic regression analysis showed that hypertension was a protective factor for (OR = 0.340, 95%CI: 0.123-0.941; P = 0.038). A high National Institutes of Health Stroke (NIHSS) score at admission (OR = 1.068, 95%CI: 1.010-1.129; P = 0.021), as well as intraoperative flat CT high⁃density sign (OR = 9.942, 95%CI: 2.631-37.567; P = 0.001), mass effect (OR = 23.564, 95%CI: 7.266-79.421; P = 0.000), and CT value ≥ 90 HU (OR = 9.714, 95%CI: 1.982-47.605; P = 0.005) were risk factors for postoperative intracranial hemorrhage. The ROC curve showed that the area under the curve (AUC) for intraoperative flat CT value ≥ 90 HU, mass effect and their combined prediction of postoperative intracranial hemorrhage were 0.82 (95%CI: 0.734-0.889, P = 0.000), 0.75 (95%CI: 0.661-0.833, P = 0.000) and 0.76 (95%CI: 0.668-0.838, P = 0.000), with sensitivity were 75.86%, 58.62% and 58.62%, and specificity were 88.31%, 92.21% and 93.51%. The predictive efficiency was highest for CT value ≥ 90 HU (t = 48.777, P = 0.000; t = 43.681,P = 0.000). Conclusions In patients with AAC⁃LVO undergoing mechanical thrombectomy, intraoperative flat CT high⁃density sign such as CT value ≥ 90 HU and mass effect can predict postoperative intracranial hemorrhage, and the predictive value of CT value ≥ 90 HU is relatively high.

Objective To compare and analyze the clinical outcomes of endovascular treatment of anterior circulation large vessel occlusion (ac-LVO) caused by large artery atherosclerosis (LAA) and simple arterial embolization. Methods From August 2020 to September 2022, 87 patients with ac - LVO hospitalized in The Second Affiliated Hospital of Bengbu Medical University were enrolled. All patients were treated with endovascular treatment, including intravenous thrombolysis, stent thrombectomy, aspiration thrombectomy or angioplasty (balloon dilatation or stent implantation). According to intraoperative findings (etiology), they were divided into LAA group (n = 32) and simple arterial embolization group (embolization group, n = 55). The primary outcome was the 90 d modified Rankin Scale (mRS) score, and the secondary outcomes were postoperative vascular recanalization rate [modified Thrombolysis Cerebral Infarction (mTICI)] and incidence of symptomatic cerebral hemorrhage 1 d after surgery. Results The proportions of patients with atrial fibrillation (χ2 = 17.672, P = 0.000) and thrombus retrieval ≥ 3 times (χ2 = 10.606, P = 0.001) in the embolization group were higher than those in the LAA group, the proportion of intravenous thrombolysis in the embolization group was less than that in the LAA group (χ2 = 5.403, P = 0.020). However, the time from onset to operation (Z = 1.111, P = 0.267), the time from admission to operation (Z = 0.149, P = 0.882), preferred surgical approach for endovascular treatment (Fisher's exact probability: P = 0.153), as well as the rate of good prognosis (mRS score ≤ 2; χ2 = 0.004, P = 0.950) and mortality (χ2 = 0.035, P = 0.851) at 90 d after surgery, the rate of postoperative vascular recanalization (mTICI grade ≥ Ⅱb; χ2 = 0.033, P = 0.856) and symptomatic cerebral hemorrhage rate 1 d after surgery (χ2 = 0.345, P = 0.557) for the secondary outcome were observed in both groups, the above differences were not statistically significant. Conclusions The efficacy and prognosis of endovascular treatment of ac-LVO caused by LAA and simple arterial embolization has the same effect and clinical prognosis.

Cell-free circulating tumor DNA (ctDNA) is synthesized by tumor cells, including metastatic tumors, and circulates in the bloodstream. Evidence suggests that ctDNA is a potential predictive and prognostic biomarker for colorectal cancer (CRC), but its predictive efficacy in detecting CRC liver metastasis (CLM) remains unclear. Additionally, its utility in the clinical setting needs further investigation. We conducted a meta-analysis to determine the utility of ctDNA as a biomarker for predicting the prognosis of CLM and investigate the relationship between CLM and ctDNA positivity. A literature search was performed in electronic databases to identify relevant studies published up to March 19, 2022. We retrieved data on overall survival (OS), disease-free survival (DFS), and recurrence-free survival (RFS) for both ctDNA-positive and ctDNA-negative colorectal liver metastasis (CLM) patients from the selected articles. Hazard ratios (HRs) were also calculated for these survival outcomes analysis was also performed. The stability of the combined meta-analysis was verified by sensitivity analysis and publication bias evaluation. Ten trials were included, and 615 patients were evaluated. In patients with CLM, pooled HRs revealed a substantial link between ctDNA positivity and RFS/DFS. Subgroup analysis revealed that ctDNA had a prospective detection value. Sensitivity analysis and publication bias evaluation indicated stable results. Although the results on pooled HR for OS suggested that ctDNA-positive patients had a shorter survival time, their pooled HRs had a relatively evident heterogeneity, and sensitivity analysis and publication bias evaluation indicated that pooled HRs were extremely unstable. In conclusion, our results demonstrate that ctDNA appears to be a prognostic biomarker for resectable CLM patients.

We deal with localized semiclassical states for singularly perturbed Kirchhoff-type equation as follows: −ε2a+εb∫R3∣∇v∣2dxΔv+V(x)v=P(x)f(v),x∈R3,-\left({\varepsilon }^{2}a+\varepsilon b\mathop{\int }\limits_{{{\mathbb{R}}}^{3}}| \nabla v{| }^{2}{\rm{d}}x\right)\Delta v+V\left(x)v=P\left(x)f\left(v),\hspace{1em}x\in {{\mathbb{R}}}^{3}, where V,P∈C1(R3,R)V,P\in {C}^{1}\left({{\mathbb{R}}}^{3},{\mathbb{R}}) and bounded away from zero. By applying the penalization approach together with the Nehari manifold approach in the studies of Szulkin and Weth, we obtain the existence of an infinite sequence of localized solutions of higher topological type. In addition, we also give a concrete set as the concentration position of these localized solutions. It is noted that, in our main results, ff only belongs to C(R,R)C\left({\mathbb{R}},{\mathbb{R}}) and does not satisfy the Ambrosetti-Rabinowitz-type condition.

Objective: To clarify the effect of controlled atmosphere on preservation of water bamboo. Methods: Cold storage under air was used as control, the sensory quality, texture （firmness, chewiness and shear force）, color （L* value and WH value）, the contents of soluble protein, lignin and cellulose, as well as the activities of phenylalanine ammonia lyase （PAL） and polyphenoloxidase （PPO） were determined under four different gas components （CA1: 2% O2+7% CO2+91% N2, CA2: 5% O2+10% CO2+85% N2, CA3: 5% O2+7% CO2+88% N2, CA4: 2% O2+10% CO2+88% N2）, then stored at 0 ℃ with the relative humidity （RH） of 85% ~ 90%. Results: Controlled atmosphere （CA） treatment could significantly slow down the decline of sensory quality, L* value and WH value of water bamboo and the consumption of soluble protein （P＜0.05）. Among these CA treatments, the effects of CA2 treatment on preservation was the best. After 90 d storage, the PAL and PPO activities of CA2 treatment were significantly lower than those of control group, CA1 and CA3 （P＜0.05）, but there was no significant difference with CA4. Moreover, the accumulation of lignin and cellulose were inhibited, but the inhibition effect of CA2 treatment on lignin and cellulose were lower than that of CA3. The firmness and chewiness of CA1 treatment were significantly higher than other treatments （P＜0.05）, but the shear force was lower than that of CA2. Conclusion: The gas components of 5% O2+10% CO2+85% N2 effectively inhibited the quality deterioration of water bamboo, showing the best effect on commodity quality after 90 days of storage, providing theoretical basis and technical support for storage of water bamboo.

The triaxial strength envelope of rocks is usually nonlinear, and the shear strength parameters obtained by the linear regression method (LRM) are highly sensitive to confining pressure. In order to enable LRM to consider the influence of confining pressure on the estimation of shear strength parameters, the confining pressure effect coefficient of triaxial strength of rocks is defined. An exponential function is constructed to express the relationship between the coefficient and confining pressure, which is also introduced into the correction of LRM. A linear regression method considering confining pressure effects (CCPE-LRM) is proposed. At the same time, a rationality test method is proposed, and a distance coefficient is defined as an index to characterize the difference between the estimated and actual values of shear strength parameters. Through the verification and analysis of the triaxial strength data of various types of rocks in the published literature, the results show that the distance coefficients of various rocks are small, and the shear strength envelopes obtained by CCPE-LRM are all close to the Mohr circles in an approximately tangent state. It indicates that the shear strength envelope obtained by CCPE-LRM can replace the ideal shear strength envelope to a certain extent, and the shear strength parameters estimated by this method are in good agreement with the theoretical shear strength parameters. These prove that CCPE-LRM LRM has a good applicability.

Layered rock slopes are the most widely distributed slopes with the simplest structure. The classification of layered rock slopes is the basis for correctly analyzing their deformation and failure mechanisms, evaluating their stability, and adopting reasonable support methods. It is also one of the essential indicators to support the evaluation of urban and rural construction suitability and the assessment of landslide hazards. However, the present-day classification methods for layered rock slopes are not sufficiently automated. In the application process of these methods, a lot of manual intervention is still needed, and sufficient strata orientation data obtained through field surveys is required, which is not effective for large-scale applications and involves high subjectivity. Thus, this study proposes a semi-automated classification method for layered rock slopes based on digital elevation model (DEM) and geological maps, which greatly reduces human intervention. On the basis of slope unit division, the method extracts structural information of slopes using DEM and geological maps and classifies slopes according to their structural characteristics. An experiment has been carried out in the northern region of Mount Lu in Jiangxi Province, and the results demonstrate the effectiveness of this semi-automated classification method. Compared to the existing manual or semi-automated classification methods, the method proposed in this article is objective and highly automated, which can meet the requirements of classification of layered rock slopes over large areas, even in the case of sparse measured orientation data.

Crop growth model describes the development and growth process of crop. Development process is the physiological age of crops, which is related to the morphological changes of crops, and is a landmark stage of crop growth to achieve qualitative change. Development process is the time indicator of crop growth model. Reasonable description of the crop development process is the premise of high accuracy of crop growth model. At present, although different crop development models have been developed and widely used in crop growth models, their simulation ability can hardly meet the needs of crop growth simulation. These models only focus on the impact of meteorological conditions in a certain period (day), but do not particularly consider the period of crop development, which may be an important factor for the low accuracy of model simulation.It is assumed that the development rate of a crop on a certain day is not only related to the meteorological conditions of that day, but also related to its development stage. The development stage of crop is represented by the date, so that the temperature-day (TAd) and development unit-day (CHUd) models are constructed. In addition, according to the principle of heat unit corrected by temperature model (THUa), the development unit corrected by temperature model (CHUa) is constructed. Based on the principle of response-adaptation of temperature model (RAM), the response-adaptation of development unit model (CHUr) is established.The adaptability of the development model for sugarcane is analyzed by using the field data of 30 agrometeorological stations in China from 1980 to 2019, and the advantages and disadvantages between the traditional development model and the reconstructed model are compared. The results show that CHUd and TAd model have better adaptability to simulate the development process of sugarcane, especially in the later stage of the development process when the temperature is decreasing. Compared with the original model (CHU), the adaptive ability of CHUa model for sugarcane decreases from seedling emergence to stem elongation but increases from stem elongation to maturity. The theoretical description of CHUr model is not tenable. Sorted by simulation ability, the order of development models is as follows: CHUd, TAd, RAM, CHU, CHUa and the heat unit (THU) model, and their simulation ability values (SCV) calculated by root mean square difference are 4.3, 3.9, 3.7, 3.3, 3.0 and 2.8, respectively.The reconstruction of the development model will further improve the CAMM and promote the development of crop growth simulation theory.

Peritoneum is the common site of colorectal cancer (CRC) metastasis. Female CRC patients with peritoneal metastases are often accompanied by ovarian metastases. It is generally believed that female colorectal cancer with peritoneal and ovarian metastases progress rapidly and have a very poor prognosis, and there is still no effective treatment at present. Although chemotherapy and targeted drugs could significantly improve the prognosis of colorectal cancer patients, there was no significant benefit in colorectal cancer patients with both peritoneal and ovarian metastases. Many studies have demonstrated that CRS combined with HIPEC can prolong the survival and improve the quality of life of these patients. This article reviews the current status of diagnosis and treatment and research progress of peritoneal and ovarian metastases in colorectal cancer.

The physical/chemical properties and synthesis methods of nanoparticles were briefly introduced, and then the type and principle of the self-assembly of nanoparticles were discussed in detail. The research progress in the application of the nanoparticle self-assembly in lithium-ion batteries was summarized, and the existing problems such as the low production efficiency and high pollution in this field were also pointed out. The future works will be focused on developing approp-riate building blocks, disclosing the self-organization mechanisms and simplifying the fabrication processes, and the simultaneous yet effective adjustion of the self-assembly processes in the materials synthesis stage for advanced battery components with hierarchical structures or functions is one of the most important approaches.

To investigate the general laws of solute transport in homogeneous and heterogeneous soil,this study conducts column experiments in the laboratory to observe and monitor hydrodynamic dispersion under different conditions.The measured breakthrough curves of solute are fitted and analyzed by the classical advection-diffusion equation (ADE).The results reveal that the solute concentration has little effect on the hydrodynamic diffusion coefficient in homogeneous soil;however,the flow rate of solute transport can promote hydrodynamic diffusion,namely that a higher flow rate can lead to a larger hydrodynamic diffusion coefficient,and the breakthrough curves can be completed faster.There is a positive correlation between the hydrodynamic diffusion coefficient and the mean particle size of the sand at a certain flow rate.In addition,the scale effect is prominent in the solute transport process in soil;generally,the hydrodynamic diffusion coefficient increases with the traveling distance.Compared with the case of homogeneous soil,the heterogeneity and different layered structures of layered soil have a more significant influence on hydrodynamic dispersion.

BACKGROUND Red bed sandstone is a set of continental or shallow lake clastic rocks in the Danxia landform. Accurate determination of Fe(Ⅱ) and Fe(Ⅲ) in red bed sandstone that indicates the redox relationship during weathering can serve as the dividing basis of weathering degree and depth of the block. During the determination of iron content by phenanthroline spectrophotometry, Fe(Ⅱ) is easily oxidized and the result is a lower value than it should be. Effective prevention of oxidation is the focus of accurate measurement of Fe(Ⅱ) and Fe(Ⅲ) content. OBJECTIVES To explore the preservation method of Fe(Ⅱ) during dissolution and establish a spectrophotometric method for the determination of Fe(Ⅱ) and total iron in red sandstone. METHODS Color reagents were added in the samples, and the samples were dissolved by hydrofluoric acid and dilute sulfuric acid, in a constant temperature water bath at 90℃. Hydroxylamine hydrochloride was used as a reducing agent, o-phenanthroline was used as a chromogenic agent, pH was adjusted by acetate-ammonium acetate buffer, and trace Fe(Ⅱ) and total iron were determined by spectrophotometer. RESULTS The detection limit of Fe(Ⅱ) was 0.002%, relative standard deviation (RSD, n=8) was less than 2%, and the standard recovery was between 92.6% and 94.7%. The Fe(Ⅱ) content of red sandstone in the Danxia landform area of Chishui was determined by this analysis method. The content of Fe(Ⅱ) ranged from 0.01% to 0.1%, the total iron content was 0.7%-1.5%, and the content of Fe(Ⅲ) calculated by subtraction was 0.7%-1.5%. The measurement results were consistent with those of X-ray fluorescence spectrometry and potassium complexate titration method. CONCLUSIONS This method uses developer and hydrofluoric acid-dilute sulfuric acid to dissolve the samples, which can effectively preserve the original Fe(Ⅱ) in sandstone. The same solution can be used for the determination of both total iron and Fe(Ⅱ) which provides a simple and accurate analysis method for various types of iron content in red bed sandstone.

On the basis of the steady state analysis of the VIENNA rectifier, an improved direct synchronous decoupling method is used to model the current inner loop, and a small amount of power compensation is added to expand the working area to adapt to different degrees of unbalanced voltage, which can reduce the DC voltage ripple and reactive power DC component under unbalanced input condition. In addition, this paper adds dead-beat control to track the reference current and selects the best duty cycle to drive the gate. The control strategy effectively realizes DC side voltage ripple elimination and power factor correction. Simulation and experiment verify the correctness of the theoretical analysis and the feasibility of the control strategy.

In order to realize the effective enrichment of phosphorus in high phosphorus converter slag, using the Ca O-Si O2-Fe2O3-P2O5-MgO-MnO slag with a P2O5content of 10% (mass fraction) as the research object, the form of phosphorus in the high phosphorous slag was studied by the laboratory hot state experiment.The effects of basicity and Fe2O3content on the enrichment of phosphorus in high phosphorus converter slag were investigated.The results show that the phosphorus element in the high phosphorus converter slag mainly exists in the form of n2CaO·Si O2-3CaO·P2O5 (n C2S-C3P) solid solution and the changes of slag basicity and Fe2O3content have no effect on the phosphorus occurrence form.The change of basicity has an effect on the production of 2CaO·Si O2.Too high or too low basicity is not conducive to the enrichment of phosphorus from slag to phosphorus-rich phase.Controlling the slag basicity in the range of 1.5-1.8 is conducive to the full enrichment of phosphorus in slag.Increasing the Fe2O3content in the slag can reduce the precipitation of 2CaO·Si O2and increase the content of P2O5in the phosphorus-rich phase, which is favorable for the enrichment of phosphorus in the slag.

In order to improve the regulation capability of the wide range output voltage and light load efficiency, this paper proposed two level control strategy. Asymmetrical Pulse Width Modulation(APWM) was used in the LLC series resonance with voltage double rectifier and a feedback controller was added to get the proper crossover frequency and enough relative stability. Phase-locked loop control(PLL) was used to track the resonant frequency. In addition, considering the high switching frequency of the secondary leakage inductance will affect the input and output voltage gain, this paper added secondary leakage inductance to the model to reduce the reverse blocking voltage of rectifier diode, which can improve the accuracy of modeling. Simulation and experiment have verified the correctness of the theoretical analysis and the feasibility of the control strategy.

Based on the traditional average current control voltage loop, this paper proposed an optimized feedforward control scheme. The voltage control loop introduced the load feedforward control and the grid voltage feedforward control to reduce the voltage overshoot in DC side. The current control loop designed as a proportional controller using error iteration algorithm, which realize floating control and optimize the dynamic response of three-phase VIENNA rectifier. The proposed load feedforward terms updated when the load step and remains constant at steady state. In addition, this paper analyzed the frequency response characteristics and validates them by simulation.

The identification and classification of marble depended mainly on the identification of rock slices and the semi-quantitative detection of minerals by X-ray Diffraction (XRD). It was found that the results of identification of rock slices were not always consistent with those of the semi-quantitative detection by XRD. Therefore, it is necessary to introduce other techniques to verify the results of thin section observation and XRD semi-quantitative analysis. 32 marble samples were analyzed by X-ray Fluorescence Spectrometer, the results and finding of which are reported in this paper. Based on the chemical composition of rock, rock impurity, magnesite, and calcareous coefficients are used to classify the marble. The results show that magnesite coefficients of calcite marble, dolomite marble, and magnesite marble are 0.01-0.13, 0.40-0.46 and 0.97-0.98, respectively. Calcareous coefficients are 0.78-0.84, 0.30-0.49 and 0.01-0.02, respectively. Different types of marble have various magnesia and calcareous coefficients, which can be used as the main basis for the division of marble types. Only the contents of SiO2+Al2O3 in rocks are less than 30% (impurity coefficient less than 1.00), then can be classified as marbles. The establishment and application of impurity, magnesia and calcareous coefficients in marble can be used to correct the inconsistent results between thin section observation and X-ray Powder Diffraction mineral semi-quantitative analysis, making marble classification more accurate.

This study established a two-dimensional mathematical model of solidification and heat transfer for a bloom with a 310 mm×360 mm cross-section using ANSYS software, which was verified by nail-shooting experiments in the narrow side of the bloom and surface temperature testing. The effect of the casting process parameters, such as superheat, casting speed, and secondary cooling intensity, on the solid fraction in the strand centerline and the solidified shell was investigated. Moreover, the optimum casting speed and the optimum solid fraction in the core of the partially solidified strand throughthe soft reduction zone were determined by the model considering the hot ductility of the high-carbon wear-resistant ball steel BU. Plant trials of BU with different casting speeds were performed to validate the theoretical model and analyze the effect of the casting speed on the segregation and shrinkage cavity of BU on a 310 mm×360 mm bloom caster equipped with final electromagnetic stirring (F-EMS) combined with mechanical soft reduction (reduction amount with 17 mm). The results show that the inner defects (e. g., center segregation, V-segregation, and shrinkage cavity) significantly improve when the casting speed is adjusted to meet the required soft reduction zone as a matter of priority; otherwise, the casting speed is only adjusted to preferentially satisfy the required F-EMS stirring region. The inner quality does not show any obvious improvement. Except for the internal cracks and the negative center segregation caused by the improper distribution of the reduction amount, the inner defects (e. g., macro segregation and shrinkage cavity) significantly improve with a casting speed of 0.52 m·min-1 and a solid fraction in the strand centerline ranging from 0.30 and 0.75 in the soft reduction zone.