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【Objective】Due to its comb filter characteristics, Sampled optical Fiber Bragg Grating (SFBG) has attracted wide-spread attention and become a new focus in the research of optical fiber grating technology. The research work on designing optical filters with high channel numbers, flat tops, and narrow pass bands is of great importance in practical situation. Consequently, an Multi-Phase Shift Interpolated Sampling optical Fiber Grating (MPS-ISFBG) filter is proposed.【Methods】ISFBG has a large number of reflection channels and can introduce multiple flat top narrow transmission channels by inserting multi-phase shift. By optimizing the location of the two π phase-shift distributions of the inserted ISFBGs, an optical filters with 41 transmission channels was designed which covers the C-band with a channel interval of 100 GHz. Each channel has a flat-top response, a narrow 3 dB bandwidth (

According to the global cancer statistics in 2022 updated by the International Agency for Research on Cancer (IARC), there were nearly 20 million new cases of cancer and 9.7 million deaths. Lung cancer was the most commonly diagnosed cancer, accounting for nearly 2.5 million new cases (12.4% of all global cancers), followed by female breast cancer (11.6%), colorectal cancer (9.6%), prostate cancer (7.3%), and stomach cancer (4.9%). Lung cancer was also the leading cause of cancer deaths, with an estimated 1.8 million deaths (18.7%), followed by colorectal cancer (9.3%), liver cancer (7.8%), female breast cancer (6.9%), and stomach cancer (6.8%). Population-based projections suggest that the number of new cancer cases will reach 35 million by 2050. Increasing the investment in prevention and control measures targeting key cancer risk factors, including smoking, obesity, and infections, could save many lives globally and bring significant economic and social returns to countries in the coming decades.

Abstract: 68Ga is one of the most clinically valuable metal positron isotopes. Producing 68Ga through a 68Ge/68Ga generator is a relatively convenient way, while the parent nuclide 68Ge is mainly produced by cyclotrons. One of the most commonly used production methods is to obtain 68Ge through proton irradiation of Ga-Ni alloy targets. Accurately simulating the 68Ge yield is of great significance for Ga-Ni alloy target preparation, cyclotron irradiation plan making and production preparation. This paper proposes a method for calculating the theoretical yield of 68Ge produced by cyclotrons based on the Monte Carlo method. The energy loss and 68Ge theoretical yield of proton beam bombardment of Ga-Ni alloy targets under different conditions are calculated. The relevant results can provide reference for Ga-Ni alloy thickness design under different energy proton beam irradiation conditions. The experimental results match well with the calculated results. Finally, the reliability of the calculation results was verified through the cyclotron irradiation experiment, indicating that the theoretical calculation is instructive to the experimental results.

In view of the low accuracy of objective automatic evaluation of fabric sewing flatness, an objective evaluation model of fabric sewing flatness based on feature parameters and deep belief network (DBN) is proposed. Firstly, image preprocessing including image grayscale processing, median filter denoising, and histogram equalization enhancement was performed on the image of the fabric sewing sample to extract the texture features of the fabric, so as to obtain a fabric feature image with higher quality and facilitate subsequent processing. Then the gray level co-occurrence matrix was constructed, and the four key feature parameters of energy, entropy, contrast and correlation of fabric image were extracted at 0°, 45°, 90° and 135°. On this basis, an automatic evaluation model of fabric sewing flatness based on DBN was constructed, and the model was trained using sewing images. Last it was verified by the extracted fabric sewing images. The results show that the evaluation accuracy of the model reaches 98.74%. Compared with the two methods of multiple linear regression model and BP network model, the proposed evaluation method can effectively evaluate the flatness of sewing objectively and provide a theoretical basis for the quality control of fabric garment appearance.

ObjectiveTo establish a system for simultaneous detection of miR-888 and miR-891a by droplet digital PCR （ddPCR）, and to evaluate its application value in semen identification.MethodsThe hydrolysis probes with different fluorescence modified reporter groups were designed to realize the detection of miR-888 and miR-891a by duplex ddPCR. A total of 75 samples of 5 body fluids （including peripheral blood, menstrual blood, semen, saliva and vaginal secretion） were detected. The difference analysis was conducted by Mann-Whitney U test. The semen differentiation ability of miR-888 and miR-891a was evaluated by ROC curve analysis and the optimal cut-off value was obtained.ResultsThere was no significant difference between the dual-plex assay and the single assay in this system. The detection sensitivity was up to 0.1 ng total RNA, and the intra- and inter-batch coefficients of variation were less than 15%. The expression levels of miR-888 and miR-891a detected by duplex ddPCR in semen were both higher than those in other body fluids. ROC curve analysis showed that the AUC of miR-888 was 0.976, the optimal cut-off value was 2.250 copies/μL, and the discrimination accuracy was 97.33%; the AUC of miR-891a was 1.000, the optimal cut-off value was 1.100 copies/μL, and the discrimination accuracy was 100%.ConclusionIn this study, a method for detection of miR-888 and miR-891a by duplex ddPCR was successfully established. The system has good stability and repeatability and can be used for semen identification. Both miR-888 and miR-891a have high ability to identify semen, and the discrimination accuracy of miR-891a is higher.

In 2011, the FDA approved ipilimumab, the first immune checkpoint inhibitor(ICI), targeting CTLA-4, opening the field of immune checkpoint therapy (ICT). ICIs can induce durable clinical responses and improve survival in selected population. However, significant challenges still remain, including mechanisms of resistance, patient selection, management of serious immune-related adverse events, and rational therapeutic combinations. This review surveys the current understanding of response and resistance to ICIs and proposes a path forward to improving efficacy and minimizing toxicities.

The separation of light actinides plays an important role in the fields of nuclear industry, environmental radiochemistry, nuclear forensics, etc. Solid phase extraction(SPE) is one of the main methods for the separation of light actinides, and the key of this method is to select adsorbents with excellent adsorption performance and good physicochemical stability. Porous metal phosphonates are a kind of inorganic-organic hybrid materials combined of metal centers and organic phosphonic acid ligands. Generally, they exhibit high specific surface area, abundant active sites and good physicochemical stability, as well as excellent adsorption properties due to the outstanding binding ability of phosphonic groups to light actinides. Therefore, they are expected to be used as adsorbents for light actinides. In this review, the synthesis and structure of porous metal phosphonates are summarized, and their application in the separation of light actinides is focused, including the adsorption properties, adsorption mechanism, the physiochemical stability and practical treatment methods of these materials, etc. In the end, the development of this field is prospected.

Extracting both global and local features from pedestrian images has become the mainstream inperson re-identification.While among most of current deep learning based person re-identification models,the relations between adjacent body parts are seldom taken into consideration during extracting local features.This may decay the capability of distinguishing different persons when they share similar attributes of local regions.To address this problem,a novel method is proposed to learn region correlated deep features for person re-identification.In our model,the output feature map of backbone network is partitioned with multiple granularities first.And then the structure information preserved local features are learned via a new designed Region Correlated Network (RCNet) module.The RCNet makes full use of the structure maintenance of average pooling and the performance advantage of max pooling,endowing local features with rich structural information.By jointly processing current feature and local features from other regions,they are strongly related to each other due to the spatial correlation.As a result,the discrimination of them is significantly enhanced.For better optimization of the whole network,the shortcut connection in deep residual networks is also employed in the architecture of RCNet.Finally,the re-identification is conducted with both global features and the local features with structural information incorporated.Experimental results show that the proposed method achieves higher matching accuracies in comparison with existing approaches on the public Market-1501,CUHK03 and DukeMTMC-reID datasets,demonstrating favorable re-identification performance.

In the current pandemic of SARS-Cov-2 (formally known as novel coronavirus disease 2019, COVID-19), the cancer treatment is particularly a challenge that must be overcome as soon as possible. Currently, the clinical data on the prevalence of SARS-Cov-2 in cancer patients is very limited, alone with constant evolving situations. To obtain existing evidence, we reviewed a wide range of medical literature and relevant websites including the National Health Commission of China. With the actual situation of Hubei Cancer Hospital, we formulated the interim guideline which was developed by all contributors from different disciplines after fully discussion, to provide the reference for treatment options on cancer patients, especially the cancer patients recovered from COVID-19 infection. This guideline highlighted the multidisciplinary team (MDT) diagnostic model, the assessment between risks and benefits prior to treatment, individualized service for patients' medical needs, and the acceptability in ethics and patients' socio-economic conditions.

The development of immune checkpoint inhibitors (ICI) has revolutionized cancer treatment. ICI stimulates the immune system to recognize and destroys cancer cells via immune checkpoint proteins. However, these drugs can also induce immune-related adverse events (irAE) in off-target organs, such as the heart. The most common manifestation of heart damage is myocarditis, and these rear off-target effects can be life-threatening. Existing data indicate that ICI induces miss-target effects through several mechanisms, including direct binding to surface proteins expressed in normal tissues, activation of T cells that cross-react with miss-target tissues, production of autoantibodies and pro-inflammatory cytokines. A better understanding of the adverse effects of cancer immunotherapy and its underlying mechanisms will help to develop biomarkers to identify at-risk patients and prevent these irAEs.

Objective To evaluate the efficacy and safety of low-dose Oxycodone and Acetaminophen Tablets in the treatment of moderate bone metastasis cancer pain and whether it is superior to the weak opioid drug codeine. Methods Seventy-eight patients were randomly treated with Oxycodone and Acetaminophen Tablets(n=52) or codeine(n=26). The initial dose of Oxycodone and Acetaminophen Tablets was 1 tablet, Q12h. According to the outbreak of pain, 1 tablet Q8h was permitted, but not more than 3 tablets per day. If there was gastrointestinal bleeding, suspected abnormal liver or kidney function, Oxycodone and Acetaminophen Tablets should be discontinued. The initial dose of Codeine was 30mg Q12h. According to the outbreak of pain, Q8h could be used. The pain control and adverse reactions were observed in the short term (72 hours) and the long term (2 weeks). Pain severity was assessed by numerical rating scale (NRS). Results Within 72 hours, the patients whose NRS score was reduced to 3 points in Oxycodone and Acetaminophen Tablets group were significantly more than those in Codeine group (88.46% vs. 45.45%, P=0.006). The long-term effect in Oxycodone and Acetaminophen group were similar to Codeine group (63.46% vs. 61.54%, P=0.868). The incidence of adverse reactions including nausea, vomiting, lethargy, constipation, etc. were low, without significant difference between two groups. Conclusion Strong opioid drugs such as oxycodone could be used for moderate bone metastasis cancer pain. It is the first time to find that low-dose Oxycodone and Acetaminophen Tablets are more effective than weak opioid drugs codeine, with acceptable safety in long-term use.

The research progress of the compressive permanent deformation of silicone rubber was reviewed, and the influences of base rubber, filler, auxiliary agent, sample size and testing environment on the compressive permanent deformation were introduced. The research direction of low compression permanent deformation of silicone rubber was also prospected. [ABSTRACT FROM AUTHOR]

Longmen - Congyi area is one of the bauxite met allogenic belts in Hen an Province. Based on chemical test of the main compositions of Corigyi bauxite deposit, the paper analyzes the change rule of elements in the bauxite deposit. The results show that the major mineral compositions of bauxite ore is di aspo re (45%-95%), followed by kaolinite and illite (4%-25%), with a small amount of siderite, pyrite, calcite and dolomite, and trace minerals such as zircon and apatite. The main chemical compositions of bauxite ore are Al2O3, SiO2, Fe2O3, TiO2 and S, accounting for 83.42% of the total, among which the Al2O3 content is 40.46% -77.59%, averagely 60.68%, SiO2 1.00%-29:54%, averagely 14.07%, with the aluminum-silicon ratio (A/S) of 1.8-65.1, averagely 4.3. Under different burial depth conditions, the larger the relative depth is, the larger the Al2O3 content and A/S ratio are. The chemical index of alteration (CIA) of the area is up to 91.16, indicating that the aluminum-bean ng rock senes in the area has undergone intense chemical weathering. [ABSTRACT FROM AUTHOR]

The research progress of oil-resistant silicone rubber was reviewed, and three main methods to improve the oil resistance of silicone rubber were introduced, which were adjusting the formula, introducing polar functional groups, and blending with other rubber. The application prospect of oil-resistant silicone rubber was also speculated. [ABSTRACT FROM AUTHOR]

The research progress of high tear strength silicone rubber is reviewed, and the methods to improve the tear strength of the rubber are introduced by adjusting the formula and blending with the other materials, and the development trend of high tear strength silicone rubber is prospected. [ABSTRACT FROM AUTHOR]

Due to the small mode field of silicon photonic chips, the large coupling loss is a road-blocker for their applications. In this work, the coupling efficiency between a silicon photonic modulator chip and a single-mode optical fiber is investigated. The mode field matching theory is analyzed at first. Then the mode field test of silicon chip and single-mode optical fiber for coupling is carried out. Next, a low-cost coupling method to improve coupling efficiency is proposed. The experimental results show that the coupling efficiency of the single-mode optical fiber and silicon photonic chip reaches 70%. The optical module is made by using this scheme, and the 4 Pulse Amplitude Modulation (PAM4) eye diagram is tested. The experimental results show that better eye diagram can be obtained. [ABSTRACT FROM AUTHOR]

The high temperature vulcanized (HTV) silicone rubber was prepared from methyl vinyl silicone rubber by adding fumed silica, hydroxyl silicone oil, hydrogen silicone oil and stearic acid. The effects of raw rubber, fumed silica, polyvinylsilicone oil and tetramethyldivinyl disilazane on the properties of HTV silicone rubber were investigated. The results showed that the Shore A hardness of silicone rubber increases from 55.5 °C to 76.5 °C with the increase of the vinyl mole fraction from 0.05% to 0.23%, the tensile strength increases from 10.7 MPa to 11.2 MPa, then decreases to 8.9 MPa, and the elong ation at break decreases from 540% to 260%, as fumed silica N20 increases from 30 phr to 55 phr, the Shore A hardness of silicone rubber increases from 50 to 70 degrees, and the tensile strength increases from 7.7 MPa to 11 MPa, the tear strength reaches the maximum of 26.3 kN/m when N20 was 40 phr in fumed silica. For the same silica in the other systems, the tear strength reached the maximum of 26.3 kN/m when N20 was 40 phr, the tear strength of silicone rubber increases with the increase of the specific surface area of fumed silica, and the hardness of silicone rubber changed little with the increase of the contents and mole fraction of vinyl in polyvinylsilicone oil, the tensile strength and tear strength increases firstly and then decreases, but the shore A hardness of silicone rubber is not change obviously with the increase of tetramethyldivinyldisilazane. When tetramethyldivinyl-disilazane is 0. 4 phr, the maximum tear strength of silicone rubber is 44.3 kN/m. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) /attapulgite(AT)composites were prepared by a solution blending method. The effect of the mass ratio of GO/AT on the adsorption capacity of the composites was investigated, and the phase composition and microstructure of the composites were analyzed. The results indicated that the composites gained a maximum adsorption capacity when the mass ratio of GO/AT was 3/4, and their adsorption rate reached 93. 06 %. The effects of adsorption time, the initial concentration of tetracycline hydrochloride, and the pH values on the removal of tetracycline hydrochloride from aqueous solution were further investigated, and the mechanism and process of tetracycline hydrochloride adsorption were explored. The adsorption behavior of the composites for tetracycline hydrochloride was found to comply with the Langmuir isothermal equation and quasi second-order kinetic model with apparent adsorption activation energy of 37. 19 kJ/mol. This indicated that the adsorption behavior was dominated by electrostatic adsorption. Moreover, the adsorption process was determined as an endothermic, spontaneous and entropy increasing process in the temperature range of this study according to the important parameters of ΔHO=7. 77 kJ/mol, ΔGO<0 and ΔSO=57. 62 J/ (mol*K). [ABSTRACT FROM AUTHOR]

The general performance requirements of non -skid coatings for flight decks are summarized. The product standards and test methods of non - skid coatings at home and abroad are analized . the research progress of polyurethane, epoxy resin and silicone coatings is reviewed, and the development trend of silicone non - skid coatings is prospected. [ABSTRACT FROM AUTHOR]

In the distributed sensor networks, individual sensors always have different FoDs, this lead the classical evidence theory can not be used. In view of this problem, this paper proposed a fault detection algorithm in the dynamic FoD using conditional probabilistic approach. Firstly, it derived the new observed evidence and its belief measure. Secondly, it used the conditional probability of new evidence to update the old belief measure. Thus, it could use the new updated belief measure to detect fault. Finally, it constructed a two-sensors-subnets model to verify this approach. Simulation results demonstrate that the proposed method shows an effective ability in dealing with the dynamic FoD and fault detection. [ABSTRACT FROM AUTHOR]

This paper first outlines the worldwide oil and gas pipeline laying situation by 2013 and industrial applications, the working characteristics and advantages of orbital pipe welding robots using the gas metal arc metal(GMAW). Then the classifications of commonly used welding seam tracking sensors are comprehensively introduced. The sensor working principles, advantages and disadvantages and the application situation in pipeline welding are analysed in details. The studies show that arc sensors and visual sensors have many advantages such as good real-time characteristic, informativeness and high tracking precision, and are most widely used in pipeline welding. Using single sensor in different process can limit the tracking precision easily, but a system with multiple sensors will greatly improve the tracking precision in oil and gas pipeline welding. A system using visual sensor and arc sensor has been used in the gas field pipeline welding in Japan and a good effect has been achieved. Finally the conclusion is drawn that suitable seam tracking sensor should be chosen according to the process features and methods, and using a variety of sensors can improve the welding seam tracking precision, which will become the focus of future researches. [ABSTRACT FROM AUTHOR]

The traditional dynamic spectrum allocation (DSA) algorithms such as coloring based and game theory based algorithms had the shortcomings of high energy consumption and computational complexity, and thus were not suitable in practical. This paper proposed a high efficiency and low energy consumption DSA scheme based on queuing theory while PU and SUs coexist in the same CRN and each PU could be either active (ON) or inactive (OFF) in any given slot. Analytical expressions of some key network parameters including the average block probability and the break probability of secondary user under the proposed scheme was given. Besides, simulations are conducted to verify the effectiveness of the proposed scheme, with advantages lower energy consumption. [ABSTRACT FROM AUTHOR]

This paper proposed a cooperative quantum-behaved particle swarm optimization algorithm with learning behavior (LCQPSO). For the problem of premature convergence of quantum-behaved particle swarm optimization (QPSO), the QPSO was improved from 2 ways. First, it adopted the strategy of cooperative searching by multi-subpopulations to enhance the global searching ability, it also ensured the population' s diversity in the later period of evolution. Second, it gave particles the ability of learning from others, which yielded population' s better local searching ability. In the experiments, this paper discussed the subpopulation' s scale and particle' s learning probability parameter, and used several well-known benchmark functions to evaluate the performance of LCQPSO, along with the comparison to PSO, QPSO, etc. The simulation results show that LCQPSO has faster convergence speed and better precision, it can avoid falling into the local extreme effectively. [ABSTRACT FROM AUTHOR]

Study on the origin of plant name and its classification will contribute to the understanding, application and utilization of medicinal plants and Chinese material medicine. A variety of textual and classified research on material medicine literature, monographs, literature and other information were consulted. We summarized that the name of traditional Chinese medicine plant was closely correlated with its morphological or some other characteristics, e. g. efficacy, flavor, product area, habitats or the name derived from homonym, legend or to commemorate someone. The study on the traceability and characters analysis has intuitive benefit in understanding the characters of medicine plants and/or Chinese material medicine, which has an important inspiration and reference function to promote the teaching and researching of the main specialized basis courses of traditional Chinese pharmacal speciality, i. e. Pharmaceutical Botany, Pharmaceutical Botany and Pharmacognosy, Chinese Medicine Identification, Chinese Material Medicine and Clinical Chinese Pharmacy. [ABSTRACT FROM AUTHOR]

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Objective; To study clinical characteristics of patients with endometrial carcinoma under 40 years old. Methods; To study endometrial carcinoma cases who were treated from December 2004 to December 2012 retrospectively. Those patients were divided into two groups, which were 20 cases (4%, 20/498) at age of less than 40 years in early onset group and 478 cases with more than 40 years age in general group. Clinical characteristics, risk factors, treatment, pathological type, histological grading, myometrial invasion, lymph node metastasis and adnexal metastasis between two groups were reviewed and compared. Results; The percentage of primary infertility patient in early onset group was 30.0% (6/20), The percentage of normal group was 4.2% (20/478). The difference was statistically significant (χ² =25.855,P =0.000). The incidence of hypertension in early onset group is lower than the normal group (χ²=7.954, P=0.003). All early onset group patients were endometrioid adenocarcinoma. The percentage of endometrioid adenocarcinoma in normal group was 78.5% (375/478), the difference was statistically significant between two groups (χ²=5.433,P=0.020),90% early onset group patients were histological grade G1,49.8% normal group patients were histological grade G1, the percentage of stage I in early onset group was 80%, the percentage of stage I in normal group was 74.1%, the difference between histological grade (Z=-8.259, P=0.000) and clinical stage (Z=-9.488,P=0.000) was statistically significant. There were no statistical significance between two groups in deep myometrial invasion, cervical invasion and lymph node metastasis, adnexal metastasis and positive abdominal dropsy cytology (P>0.05). Conclusions: Young women occupy a certain proportion of endometrial cancer, infertility is a high risk factor for endometrial cancer whose age is under 40 years, major pathological type is endometrioid adenocarcinoma, histological grade tend to be Gl, young patients tend to be diagnosed at an early stage, deep myometrial invasion, cervical invasion and lymph node metastasis, adnexal metastasis and positive abdominal dropsy cytology are similar to the elderly patients, etc. [ABSTRACT FROM AUTHOR]

The concept of functional dependencies plays an important role in database theory since it is the basis of normal forms that are used to produce well-design schema. Due to the complexity of the semi-structured XML model, it is a challenge to define the functional dependencies and study the nature of those dependencies such as their capability of representation, logical implication and corresponding normal forms. The previous works in this area are surveyed and the approaches they deployed are described. Particularly, the paper focus on the comparison of functional dependencies definitions, the problem of logical implication and the discovery of dependencies. At last, some novel problems referring to dependencies such as relationship between value and type in shortly are discussed. [ABSTRACT FROM AUTHOR]

To enhance rapeseed germplasm and improve rapeseed variety with resistance to tribenuron-methyl, seeds of Zhongshuang 9 (Brassica napus) were treated with 0.4%, 0.8%, 1.0% and 1.2% of EMS (ethyl methansulfonate) solution respectively. Results showed that (1)1. 0% of EMS was optional for mutagenesis and the phenotype variation in four M2 populations were 11.26%, 14.82%, 27.19% and 12.38% respectively. (2) Different concentrations of EMS had different effects on organs. (3) Three mutants with resistance to tribenuron -methyl were with mutation frequency about 0.0001. The M2 mutant library, including mutants of cotyledons, leaves, flowers, plant-types, siliques, was available for genetic studies and breeding in rapeseed. [ABSTRACT FROM AUTHOR]

To alter the traditional large caliber naval gun flanking path shell-feeding mode which was complex, an abdominal shell-feeding method using center single line shell-swinging mechanism was proposed. According to the dynamic characteristics analysis of the abdominal shell-swinging mechanism, the secondary coupling term of the longitudinal deformation in the description of deformation field was considered to establish the first order approximation rigid- flexible coupling dynamics model. Then the iterative learning input shaping control method was proposed based on the first-order approximation theory, which joint PD feedback control to study the residual vibrations suppression of the abdominal shell-swinging arm. Numerical simulation of the residual vibrations control on different fire angles show that recursive learning input shaping method has a significant inhibitory effect to the vibrations on the case of large deformation. [ABSTRACT FROM AUTHOR]

The characteristics of non-smoothness and uncertainty of gearbox fault vibration signal lead to the low accuracy of gearbox fault diagnosis. To address this problem, a gearbox fault diagnosis method based on local mean decomposition (LMD) cloud model feature extraction combined with particle swarm optimization (PSO) kernel extreme learning machine (KELM) is proposed. Firstly, the fault vibration signal is decomposed by LMD to obtain several PF components, and the PF components with higher correlation are screened out using the correlation coefficient principle. Secondly, the screened PF components are input into the cloud model, and the feature vectors are extracted using the inverse cloud generator and input into PSO-KELM for fault diagnosis. Finally, the performance of the method is analyzed using the measured data of the QPZZ-Ⅱ test-bed gearbox. The results show that the recognition accuracy of the method is 97.65%, and compared with various methods this method has the best recognition performance.

With the two major development objectives of “emission peak” and “carbon neutrality” proposed, nuclear energy, as a full-fledged clean energy, will play an increasingly important role in China’s energy structure. As one of the most important nuclear fuel resource, uranium resources are the cornerstone of the sustainable development of nuclear power. With the increasing scarcity of terrestrial uranium resources, an efficient utilization of marine uranium resources has then become an effective means to ensure a long-term and adequate supply of nuclear fuel. However, uranium extraction from seawater faces a huge challenge of severe marine biofouling. A large number of marine microorganisms damage the structure of the uranium extraction material, resulting in a significant reduction in mechanical properties and adsorption properties of the material. Therefore, the development of uranium adsorption materials with anti-biofouling activity is the key to extract uranium from seawater under a real marine environment. This paper comprehensively summarizes the research and development of various anti-biofouling uranium extraction materials in recent years, as well as the mechanism of different types of anti-biofouling materials. Combining the development status quo, the prospects for the further development of anti-biological fouling uranium extraction materials are put forward.

The KNO3-based water-soluble salt core was prepared using 70%KNO3-30%KCl (mole fraction) as a matrix material and glass fiber as a reinforcing material by stirring casting method. The effects of different glass fiber contents on the bending strength, impact toughness, water solubility rate and hygroscopic rate of the water-soluble salt core were compared and analyzed. The scanning electron microscopy and energy spectrometer were used to analyze the microstructure characteristics of the water-soluble salt core strengthened by glass fiber. The results show that with the increase of glass fiber content, the bending strength and impact toughness of the salt core are increased, and the water solubility rate and moisture absorption rate are gradually decreased. When the mass fraction of glass fiber is 30%, the salt core has the largest bending strength of (38.85±0.61) MPa and impact toughness with (2.13±0.1) kJ/m2, and the water solubility rate is still as high as (476.5±12.0) g/(min·m2), and the moisture absorption rate is (0.085±0.007)%. The microanalysis shows that the glass fibers are evenly distributed among the matrix of KNO3-based water-soluble salt core, which significantly refines the KCl primary phase. The average grain size of KCl primary phase is reduced from 57.89 μm to 24.13 μm, which is the main strengthening mechanism of the salt core. The crack will deflect when encountering glass fibers during the crack propagation, and the fiber pull-out is also observed, which is the main toughening mechanism of the salt core.

BACKGROUND Usually, laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS) analysis is equipped with a closed ablation cell. It cannot be used for non-destructive analysis of the large-size samples which exceeds the size of the cell. OBJECTIVES To realize directly in situ non-destructive analysis of major and trace elements in the large-size samples. METHODS Based on the self-designed open sample collection port, combined with the gas exchange device, an open LA-ICP-MS analysis method was established. Taking the large-size ceramic disc sample as an example, samples can be directly determined for major and trace elements in an air environment without being broken. RESULTS Analyte aerosols produced by laser ablation were collected and sucked by open sample collector. The air in the aerosols was replaced via transfer tube by high purity argon in a gas exchange device, the analyte aerosols were then transferred into ICP-MS for detection. After non-destructive analyses by this method, large-size ceramic samples were broken and analyzed by traditional LA-ICP-MS. Relative deviations of most of 51 elements detected by the two methods were less than 10%. Only part of elements (such as P, Be, Sc, Y, La, Sm, Eu, Dy, Hf, W, etc.) had relative deviations higher than 20%, because of the extremely low contents. CONCLUSIONS The open LA-ICP-MS method is suitable for in situ non-destructive determination of major and trace elements in the large-size samples.

BACKGROUND Cadmium is a volatile element with chalcophile affinity. In the marine environment, Cd is a micronutrient element, while in the ecological environment and agricultural soil environment, Cd is a toxic element. Therefore, Cd isotopes have been used in marine science, earth science, environmental science, and agricultural scientific research, and show great application potential. OBJECTIVES To summarize the high-precision analytical technology and applications of Cd isotopes in different research fields. METHODS The recent research progress in digestion methods, separation and purification of Cd, and double-spikes calibration methods for organic matter-rich environmental samples, plant samples and biological samples were summarized. RESULTS For organic matter-rich samples including environmental, plant and biological samples, microwave digestion, high-pressure ashing and perchloric acid digestion can eliminate the influence of organic matter in Cd isotope analysis. Combined AG MP-1(M) resin with hydrochloric acid leaching system can effectively separate the matrix and interfering elements, which will not result in Cd isotope fractionation. The precision of Cd isotope with 111Cd-113Cd isotope double-spike correction was around 0.1εCd/amu. The application of Cd isotopes in marine science, geoscience, environmental science, and agricultural science were also summarized in this paper. Cadmium isotopes were used successfully for building marine biological geochemistry cycles, inversion of ancient marine environments and primary productivity change. In sulfide deposits, Cd isotopes were used to trace the evolution of ore fluids and the source of ore metals, and to discriminate different deposit types. In environmental systems, Cd isotopes were applied to distinguish Cd pollution sources, and to investigate Cd sources, migration, circulation and storage mechanisms in agricultural sciences. CONCLUSIONS The research of the high-precision Cd isotope analytical method and Cd isotope fractionation mechanism and model, will promote to establishment the tracer system of Cd isotope biogeochemistry fractionation and innovative development of non-traditional stable isotope geochemistry.

Cadmium is a typical chalcophile element which occurs in various sulfide deposits. In the environmental system, cadmium as the nutritional requirement is utilized for the growth of microorganisms, and its cycle is greatly affected by the biological process. Several recent publications have shown that mass differences between Cd isotopes result in isotopic fractionation during the evaporation/condensation processes, biological and inorganic processes. These results demonstrate that Cd isotopes can be used as a tracer in geosciences and environmental sciences. The Multiple Collector-Inductively Coupled Plasma-Mass Spectrometry (MC-ICP-MS) has successfully been used for high-precision measurements of cadmium isotopic compositions in the geological samples, which makes a rapid advance in the geochemical research of the cadmium isotope. In this paper, based on current publications, a review of the cadmium isotopic system is provided in detail, with emphasis on the geochemical behaviour of cadmium and its isotope fractionation mechanism, the distribution characteristics in the natural reservoirs, analytical technique and the applications in the geosciences and environmental sciences. The geochemical research of the cadmium isotope is just in its infancy; conducting an investigation into the cadmium isotope fractionation mechanism, the distribution characteristics in natural reservoirs and a unified cadmium isotope standard calibration system could promote the application of the cadmium isotope in geosciences and environmental sciences.

Thermal evolution of these main Paleozoic shale source rocks were modeled based on the heat flow history and sedimentary burial history. The Lower Cambrian Qiongzhusi source rock began to produce petroleum and entered its oil generation peak in the Early Silurian rapidly, nevertheless, the hydrocarbon generating process was stationary during Middle Silurian-Early Permian. The matured stage of the Lower Cambrian Qiongzhusi source rock changed from oil into wet gas in Middle Triassic and from wet gas into dry gas in Early Jurassic. The main gas generation period of the kerogen source rock was from Middle Triassic to Early Cretaceous. The Lower Silurian Longmaxi source rock began to produce petroleum in Permian, the main gas generation period of the kerogen was from Middle Jurassic to the Middle stage of Early Cretaceous, however, the crude oil cracking gas was produced during the late stage of Late Jurassic-the early stage of Late Cretaceous. The Lower Silurian Longmaxi Formation is the best favorable target for shale gas exploration and development in the Southeastern Sichuan Basin. [ABSTRACT FROM AUTHOR]

In magnetic resonance examination, the interaction between implants and the radio frequency (RF) fields induces heating in human tissue and may cause tissue damage. To assess the RF-induced heating of implants, three steps should be executed, including electromagnetic model construction, electromagnetic model validation, and virtual human body simulations. The crucial step of assessing RF-induced heating involves the construction of a test environment for electromagnetic model validation. In this study, a hardware environment, comprised of a RF generation system, electromagnetic field measurement system, and a robotic arm positioning system, was established. Furthermore, an automated control software environment was developed using a Python-based software development platform to enable the creation of a high-precision automated integrated test environment. The results indicate that the electric field generated in this test environment aligns well with the simulated electric field, making it suitable for assessing the RF-induced heating effects of implants.

In MRI examination, RF heating of implants will affect the safety of implant wearers. The conductivity of various tissues in the human body is significantly different, and the medium conductivity will affect the distribution of the RF electric field. Therefore, it is necessary to study the RF heating of different medium conductivity. Based on the analysis of the principle of MRI RF heating, this study build the model of the bird cage coil, ASTM standard phantom and lead, and the conductivity of several typical human tissues is selected as the conductivity in the experiment. Then calculate the power deposition of the lead at 64 MHz. The results show that the medium conductivity has no effect on the distribution of electric field and power deposition, and the hot spot distribution remains unchanged under different conductivity; The smaller the conductivity is, the larger the power deposition of the lead is, and the greater the temperature rise of the lead caused by RF heating is; The change of conductivity and power deposition is approximately linear. At the limit of 2 W/kg whole body specific absorption rate(SAR), the conductivity decreases, and the wire power deposition increases sharply.