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Using aeolian sand(AS)for backfilling can realize local material extraction and turn waste into treasurethe, and realize coordination of green mining and AS control.The AS filling mining is mainly applied to the backfilling of goaf under Highway, backfilling mining of coal mine and metal mine.Grouting and sand injection in the goaf, solid backfilling mining, high water backfilling mining and cemented backfilling mining are developed.Long wall backfilling mining, strip backfilling mining and roadway backfilling mining are adopted.The research on the properties of cemented AS backfilling materials focused on slurry fluidity and backfill strength.In this paper, the rheological properties of cemented AS slurry with different proportions and curing times are analyzed, and cemented AS backfills are toughened by using polypropylene fiber.The results showed that the rheological parameters of cemented AS slurry increased with the curing time, and the addition of fiber significantly improved the brittleness characteristics of cemented AS backfills.

Gymnocypris eckloni (G. eckloni), a cold-water economic fish, is widely cultivated in southwestern China. The increase in extreme summer weather conditions owing to global warming can significantly affect their survival and health. The fish intestine and its microbiota are closely associated with fish feeding and growth, nutritional metabolism, and immune defense. However, the mechanisms underlying the changes in the G. eckloni intestine and its microbiota under acute heat stress remain unknown. In this study, we investigated the effects of acute heat stress on the G. eckloni intestine employing histology, plasma biochemical indices, transcriptomics, and 16S rDNA sequencing. Histological analysis showed that acute heat stress induced significant morphological damage to the intestine, with microvilli detachment and mitochondrial abnormalities in the ultrastructure. Biochemical indicators associated with stress (reactive oxygen species and catalase), inflammation (interleukin-1β and tumor necrosis factor-α), and intestinal permeability (diamine oxidase and lipopolysaccharide) were significantly elevated after acute heat stress, indicating an intestinal inflammatory response and disruption of barrier function. Many DEGs were mined by transcriptomic analysis, with tfrc, pfkp, egln1 enriched in the HlF-1 signaling pathway, hsp70, hsp90aa1 and hspa4 enriched in the Antigen processing and presentation pathway, pmm1, pfkfb3 and hk1 enriched in the Fructose and mannose metabolism patyway. The HIF-1 signaling pathway is a crucial regulatory pathway during acute heat stress in the G. eckloni intestine, while significant downregulation of genes associated with adaptive immunity (mica, hla-dpa1, hla-dpb1, and hla-dqb2) suggested impaired immune function. Additionally, the composition of the intestinal microbiota was dominated by Aeromonas, Citrobacter, and Acinetobacter in the control group; but there was a significant decrease in the abundance of Citrobacter and Acinetobacter, and a significantly increased in Shewanella and Hafnia-Obesumbacterium after acute heat stress. Correlation analyses revealed that changes in the abundance of Hafnia-Obesumbacterium, Buttiauxella, and Pseudomonas were closely associated with changes in gene expression associated with stress, inflammation, and immunity. These results comprehensively demonstrate the adaptive mechanisms of the G. eckloni intestine in response to acutely high temperatures and provide a theoretical basis for the future advancement of artificial culture of cold-water fish.

The behavioral interaction between artificial intelligence and consumers can bring consumers multifaceted experiences, which are of great value for enterprises to improve brand management and adjust and optimize market strategies. In this paper, we construct a gray multiple linear regression model by combining the classical multiple linear regression model and gray system theory. Taking consumers as the research object, we design a questionnaire and carry out the reliability test to obtain the data related to the experience brought by behavioral interaction with consumers and the brand management and marketing strategy of enterprises. Finally, this paper takes AI and consumer behavioral interaction as the independent variable and corporate brand management and marketing strategy as the dependent variable. It carries out regression analysis to explore the influence of the independent variable on the dependent variable. The results show that: corporate brand management = 1.879 + 0.317*sensory experience + 0.283*emotional experience + 0.168*thinking experience + 0.221*personalized experience − 0.187*privacy concerns, and corporate market strategy = 1.943 + 0.285*sensory experience + 0.266*emotional experience + 0.191*thinking experience + 0.307*personalized Experience + 0.144*Privacy Concerns. The research results of this paper are of strategic significance to help enterprises understand the significance of the interaction between AI and consumer behavior, use AI to understand consumer groups, maintain good brand management, and adjust market strategies in a timely manner.

The burgeoning realm of Internet technology has ushered e-commerce into a pivotal economic role. However, navigating the myriad risks inherent in e-commerce operations is vital for the sustained growth of businesses in this sector. This study melds economic management principles with a deep dive into e-commerce risk management, focusing on predictive strategies and mitigation measures. We commence by dissecting the principal risk categories within e-commerce operations. Subsequently, we employ Structural Equation Modeling (SEM) and Particle Swarm Optimization-Generalized Regression Neural Network (PSO-GRNN) for quantitatively dissection of these risk factors. Our findings pinpoint internal, technological, and operational management risks as the critical triad influencing e-commerce strategic operations. Remarkably, the PSO-GRNN model’s risk prediction accuracy stands at 93.62%, outstripping conventional models significantly. Through this research, we offer a robust framework for e-commerce entities to enhance their strategic foresight and resilience, aiding in optimizing their strategic maneuvers.

The 5W2H management model, rooted in World War II, stands out for its simplicity and effectiveness in enterprise management, offering considerable advantages in strategy planning and execution. This study focuses on the model’s role in enhancing strategic economic management within businesses, combining qualitative and quantitative analyses of various enterprises’ strategic management frameworks. Implementing the 5W2H model led to notable enhancements in strategic definition, implementation efficiency, and tangible achievements. Specifically, businesses observed a 20% improvement in achieving strategic objectives, a 15% faster strategy implementation, and a 25% increase in strategic engagement among employees. Additionally, the model proved instrumental in improving internal communication, fostering better teamwork, and optimizing the allocation of resources. Our findings affirm the significant value of the 5W2H model in refining corporate strategy formulation and execution, highlighting its essential place in modern enterprise management practices.

The application of phase change materials (PCM) in building energy saving is limited by the cost and performance of PCM carriers. Using solid waste as a PCM carrier can reduce cost and environmental impacts. In this study, lightweight and porous titanium-bearing blast furnace slag (Ti-BFS) was innovatively used as PCM carrier to prepare paraffin/Ti-BFS phase change aggregate (PTA) by vacuum impregnation, and then PTA was used to develop thermal energy storage cement mortar by replacing sand. The microstructure and performance of aggregate and mortar were also investigated. The results indicated that PTA has a paraffin loading rate of 21.9%, latent heat of 65.7 J/g for melting and 65.0 J/g for freezing, and good chemical compatibility. The microstructure reveals that PTA has good compatibility with cement matrix. Compared with ordinary cement mortar, a reduction percentage of 28-day compressive strength, dry density and thermal conductivity at 100% PTA substitution rate are respectively 39.8%, 29.1% and 52.5%. However, a significant capacity to weaken temperature fluctuation was observed.

In order to realize the resource utilization of peony stamens, the effects of peony stamen protein on the texture, dynamic rheological properties, disulfide bonds, surface microstructure and secondary structure of dough and gluten proteins were studied using soybean protein isolate (SPI) as a reference. The results showed that peony stamen protein could significantly improve the hardness, stickiness and chewiness of dough, and the effect of addition of less than 6% of peony stamen protein was more pronounced than that of SPI. Addition of peony stamen protein increased the storage and loss moduli and consequently the viscoelasticity of dough. The effect of peony stamen protein on the formation of gluten protein network structure was basically the same as that of SPI. Under scanning electron microscopy (SEM), gluten proteins added with 6% of peony stamen protein exhibited a compact network structure consisting of many deep pores. In the presence of peony stamen protein, the total proportion of the relative stable secondary structures of α-helix and β-sheet reached the maximum value of 59.32%, and the content of disulfide bonds increased by 89% compared with the blank group. In conclusion, peony stamen protein can effectively promote the formation of gluten protein network structure and improve the quality of dough, and therefore can be used in the production of flour products with high viscoelasticity requirements.

In aquaculture, the traditional method for hatching Pelodiscus sinensis eggs needs further investigation. Here, we developed a medium-free incubation method for hatching P. sinensis eggs and evaluated its differences from the traditional vermiculite incubation method and the effects of light on it. We found that medium-free incubation had no significant effects on hatching success, body weight, carapace length, carapace width, plastron length, plastron width, and righting response time of P. sinensis compared with those under traditional vermiculite incubation, irrespective of thermostatic or fluctuating temperature conditions. Furthermore, light treatment significantly shortened the incubation period and negatively affected body weight, carapace length, carapace width, plastron length, and righting response time during medium-free incubation. Additionally, this study is the first to report the phenomenon of egg-hatching synchrony in P. sinensis. Overall, our results provide basic data and novel insights for improving the method for hatching P. sinensis eggs.

Objective To summarize the clinical manifestations, laboratory examination, imaging examination, genetic test, treatment and prognosis of scrub typhus combined with central nervous system (CNS) infection. Methods and Results The clinical data of 4 cases of scrub typhus encephalitis diagnosed and treated from October to November in Tianjin Huanhu Hospital were analyzed. The main clinical manifestations were eschar and lymphadenopathy (4 cases), headache (4 cases), nausea and vomiting (3 cases), fever (3 cases), rash (3 cases), and mental behavior disorder (3 cases); laboratory examination of hepatic in 3 cases were abnormality. Three patients underwent lumbar puncture of cerebral spinal fluid (CSF), including 3 cases with elevated pressure, 2 with elevated white blood cell count, 3 with elevated protein quantification, and 3 with abnormal immune function. Head MRI examination in 3 cases were normal, and one case showed a slightly linear hyperintensity of FLAIR in the bilateral occipital lobes. Metagenomic next⁃generation sequencing (mNGS) of CSF was completed in 3 patients, and Orientia tsutsugamushi was detected in all of them. All 4 cases were diagnosed as scrub typhus encephalitis and recovered after effective antibiotic treatment. Conclusions The clinical manifestations of scrub typhus combined with CNS infection are not specific, so it is necessary to be vigilant against the occurrence of scrub typhus in patients with CNS infection of unknown etiologys. In particular, scrub typhus should be considered during the epidemic season, if there is a history of farm work or suburban activities.

Introduction: Bone morphogenetic proteins (BMPs) play a crucial role in bone formation and differentiation. Recent RNA-Seq results suggest that BMPs may be involved in the sex differentiation of P. sinensis, yet more relevant studies about BMPs in P. sinensis are lacking.Methods: Herein, we identified BMP gene family members, analyzed the phylogeny, collinear relationship, scaffold localization, gene structures, protein structures, transcription factors and dimorphic expression by using bioinformatic methods based on genomic and transcriptomic data of P. sinensis. Meanwhile, qRT-PCR was used to verify the RNA-Seq results and initially explore the function of the BMPs in the sex differentiation of P. sinensis.Results: A total of 11 BMP genes were identified, 10 of which were localized to their respective genomic scaffolds. Phylogenetic analysis revealed that BMP genes were divided into eight subfamilies and shared similar motifs (“WII”, “FPL”, “TNHA”, “CCVP”, and “CGC”) and domain (TGF-β superfamily). The results of the sexually dimorphic expression profile and qRT-PCR showed that Bmp2, Bmp3, Bmp15l, Bmp5, Bmp6 and Bmp8a were significantly upregulated in ovaries, while Bmp2lb, Bmp7, Bmp2bl and Bmp10 were remarkable upregulated in testes, suggesting that these genes may play a role in sex differentiation of P. sinensis.Discussion: Collectively, our comprehensive results enrich the basic date for studying the evolution and functions of BMP genes in P. sinensis.

Northern snakehead, Channa argus (C. argus), is an important economic and ecological fish species. The wild population of the species was sharply declined in the last decade. A high-quality reference genome could lay a solid foundation for the genetic and conservation studies for C. argus. In this work, we report a chromosomal genome assembly with PacBio and Hi-C technology using the albino northern snakehead, a color variety of C. argus. A 644.1-Mb genome with 24 chromosomes was obtained with a contig and scaffold N50 of 11.78 and 27.8 Mb, respectively. We inferred that C. argus diverged from A. testudineus around 85.6 million years ago. 514 expanded gene families and 214 positively selected genes were identified in the C. argus genome. The chromosome-level genome provides a valuable high-quality genomic resource for population, as well as genetic and evolutionary studies for C. argus and other species in Channidae.

Objectives To explore the implementation approach of Chinese cultural connotations in style design of cruise ships.Methods This paper presents the design concept of a "fusion of Chinese culture and contemporary spirit", and summarizes the design principles and processes of a cruise ship from the perspective of design art. The main principles are: appearance and internality coordination, entirety and elements coordination, characteristics and framework coordination, rationality and perception coordination.Results Based on the methods and principles of cruise ship modeling design with Chinese cultural connotations, and aiming at the design modeling and characteristics of modern cruise ships, this paper systematically divides cruise ships into four main design styles, namely, classical style, new Chinese style, modern style, and elegant style.Conclusions Combining with a large number of design examples, four design styles are summarized and analyzed, which provides a direction for the style design of domestic cruise ships.

Porous magnesium oxysulfate (MOS) cement pastes were successfully fabricated by injecting presaturated bentonite into modified MOS cement paste. Their pore structure and hardened performance were investigated. The results indicated that the 20MgO-MgSO4·7H2O-18H2O system modified by citric acid (C6H8O7⋅H2O) and ethylene diamine tetraacetic acid was suitable to fabricate porous MOS cement paste. Bentonite slurry led to significant refinement of pores, generating nanosized pores in MOS cement pastes. When volume replacement of bentonite slurry in MOS cement paste rose between 0 and 60%, pore size corresponding to the peak in the pore size distribution curve of MOS cement-based materials decreased from 180.0 nm to 22.8 nm and then increased to 163.0 nm, and the porosity linearly increased from 21.1% to 58.1%. These small pores caused the successful preparation of porous MOS cement paste with dry bulk density of 760–1650 kg/m3, compressive strength of 7.8–69.8 MPa, and thermal conductivity of 0.25–0.85 W/(m·K).

Nanog is a homeodomain-containing transcription factor, and it plays a vital role in maintaining the pluripotency of embryonic stem cells. Nanog’s function has been well studied in many species. However, there is lack of reporting on the Nanog gene in reptile. Here, we identified a 1032 bp cDNA sequence of a Nanog gene in Pelidiscus sinensis, known as PsNanog. PsNanog has a highly conserved HD domain and shares a high identity with that of Chelonia mydas and the lowest identity with Oryzias latipes. Similarly, PsNanog presented a tight cluster with C. mydas Nanog, but was far from those of teleosts. Additionally, we cloned a length of 1870 bp PsNanog promoter. Dual luciferase assay showed that the DNA fragment of −1560 to +1 exhibited a high promoter activity. The RT-PCR and RT-qPCR results showed that PsNanog was predominantly expressed in ovary, and then in testis. The in situ hybridization and immunohistochemical analysis showed that PsNanog was expressed in the early primary oocytes and the cytoplasm of the cortical region of stage VIII oocytes in ovary, and distributed in most stages of germ cells in testis. Collectively, the results imply that PsNanog probably has the conserved function in regulating germ cell development across phyla and is also a pluripotent cell gene and expressed in germ cells, which is similar to that in teleosts and mammals.

Spats1 (spermatogenesis-associated, serinerich 1) has been characterized as a male-biased gene which acts an important role in the germ cell differentiation of mammals. Nevertheless, the function of Spats1 in the Chinese soft-shelled turtle (P. sinensis) has not yet been reported. To initially explore the expression of Spats1 in P. sinensis and its response to sex steroid treatment, we cloned the CDS of Spats1 for the first time and analyzed its expression profile in different tissues, including the testes in different seasons. The Spats1 cDNA fragment is 1201 base pairs (bp) in length and contains an open reading frame (ORF) of 849 bp, which codes for 283 amino acids. Spats1 mRNA was highly expressed in the testes (p < 0.01) and barely detectable in other tissues. In P. sinensis, the relative expression of Spats1 also responsive to seasonal changes in testis development. In summer (July) and autumn (October), Spats1 gene expression was significantly higher in the testes than in other seasons (p < 0.05). Spats1 mRNA was found to be specifically expressed in germ cells by chemical in situ hybridization (CISH), and it was mainly located in primary spermatocytes (Sc1), secondary spermatocytes (Sc2) and spermatozoa (St). Spats1 expression in embryos was not significantly changed after 17α-methyltestosterone (MT)and 17β-estradiol (E2) treatment. In adults, MT significantly induced Spats1 expression in male P. sinensis. However, the expression of Spats1 in testes was not responsive to E2 treatment. In addition, the expression of Spats1 in females was not affected by either MT or E2 treatment. These results imply that Spats1 is a male-specific expressed gene that is mainly regulated by MT and is closely linked to spermatogenesis and release in P. sinensis.

In aquaculture, the Chinese soft-shelled turtle (Pelodiscus sinensis) is an economically important species with remarkable gender dimorphism in its growth patterns. However, the underlying molecular mechanisms of this phenomenon have not been elucidated well. Here, we conducted a whole-transcriptome analysis of the female and male gonads of P. sinensis. Overall, 7833 DE mRNAs, 619 DE lncRNAs, 231 DE circRNAs, and 520 DE miRNAs were identified. Some “star genes” associated with sex differentiation containing dmrt1, sox9, and foxl2 were identified. Additionally, some potential genes linked to sex differentiation, such as bmp2, ran, and sox3, were also isolated in P. sinensis. Functional analysis showed that the DE miRNAs and DE ncRNAs were enriched in the pathways related to sex differentiation, including ovarian steroidogenesis, the hippo signaling pathway, and the calcium signaling pathway. Remarkably, a lncRNA/circRNA–miRNA–mRNA interaction network was constructed, containing the key genes associated with sex differentiation, including fgf9, foxl3, and dmrta2. Collectively, we constructed a gender dimorphism profile of the female and male gonads of P. sinensis, profoundly contributing to the exploration of the major genes and potential ncRNAs involved in the sex differentiation of P. sinensis. More importantly, we highlighted the potential functions of ncRNAs for gene regulation during sex differentiation in P. sinensis as well as in other turtles.

The current building’s energy supply chain model has the characteristics of high complexity, time-consuming, poor accuracy, and high pollution coefficient. In this paper, a renewable building’s energy supply chain model based on LCA is proposed. Based on the definition of planned supply chain, procurement, construction and delivery process, the operation reference model of renewable green building’s energy supply chain is analyzed. According to the analysis of LCA, the life cycle stage set of renewable green building’s energy supply chain is obtained. A renewable green building’s energy supply chain model with economic and low-carbon comprehensive objectives is obtained by combining the economic goal-oriented model with the low-carbon goal-oriented model and introducing the life cycle stage set. The experimental results show that the modeling complexity of the model is low and the time-consuming is less. The model fits the actual situation well. The pollution coefficient of the model is smaller than that of the current model. It is practical and provides technical reference for the field of green building.

Ten acridones isolated from Atalantia monophylla were evaluated for effects on Alzheimer’s disease pathogenesis including antioxidant effects, acetylcholinesterase (AChE) inhibition, prevention of beta-amyloid (Aβ) aggregation and neuroprotection. To understand the mechanism, the type of AChE inhibition was investigated in vitro and binding interactions between acridones and AChE or Aβ were explored in silico. Drug-likeness and ADMET parameters were predicted in silico using SwissADME and pKCSM programs, respectively. All acridones showed favorable drug-likeness and possessed multifunctional activities targeting AChE function, Aβ aggregation and oxidation. All acridones inhibited AChE in a mixed-type manner and bound AChE at both catalytic anionic and peripheral anionic sites. In silico analysis showed that acridones interfered with Aβ aggregation by interacting at the central hydrophobic core, C-terminal hydrophobic region, and the key residues 41 and 42. Citrusinine II showed potent multifunctional action with the best ADMET profile and could alleviate neuronal cell damage induced by hydrogen peroxide and Aβ1-42 toxicity.

Solution mining of rock salt is one of the important methods to obtain salt, which is a necessity of human life and an important raw material of industry. In solution mining, water-soluble heavy metals within rock salt will migrate to the surface environment with mother solution and remain in subsequent salt products, which may contaminate the surface environment and endanger human health. Thus, it is of great importance to analyze water-soluble heavy metals in rock salt. However, water-soluble heavy metals, such as Cu, Pb, Zn, Cd, have much lower abundances than salt. The high content of salt will affect the atomization efficiency of Inductively Coupled Plasma-Optical Emission Spectrometer (ICP-OES), making it difficult to directly quantify these metals. In this study, sulfhydryl cotton was employed as the absorbent to separate and enrich Cu, Pb, Zn, Cd in rock salt. Experimental conditions such as pH, concentration and volume of eluent were optimized. The results indicated that good adsorption efficiency was achieved at pH 7, and adsorbed metals could be quantitatively eluted with 7 mL 15%HCl. Meanwhile, Na had no influences on the adsorption or desorption processes. The recoveries of Cu, Pb, Zn and Cd in desorbed solution are above 92.2%, and only 0.04% for Na, realizing the separation of heavy metals from Na and meeting the requirements for the detection of heavy metals by ICP-OES.

Commercially pure(CP) Ti fabricated by 135° ECAP and swaging was annealed at 100, 150, 200, 250, 300, 350, 400, 450℃ and 500℃ for 1h, respectively. The microstructure and properties of annealed commercially pure Ti were investigated by transmission electron microscopy, scanning electron microscopy, uniaxial tensile test and microhardness test. The results show that when annealing temperature is below 400℃, dislocation density reduces gradually and grain boundary becomes clear, no obvious change occurs in the microstructure,ultimate tensile strength and microhardness decrease slightly and no obvious increase occurs in the elongation;when annealing temperature is above 400℃, recrystallization occurs with the increase of annealing temperature, and the grain size increases obviously, the average size is about 5μm, the ultimate tensile strength and microhardness decrease significantly and elongation increases at the same time. The tensile fracture shows the tensile fracture of annealed commercial pure Ti by ECAP and swaging is ductile fracture. With the increase of annealing temperature, the size and depth of dimples increase.

There is a significant impact of ablation angle on the anti-ablation performance of C/C composites. A self-designed oxygen-kerosene ablation system was employed to study the ablation behavior and mechanism of C/C composites. Typical ablation angle of the experiment was 90°, 60°, 45° respectively, and particle concentration of the gas-solid two-phase ablation flow was 1.37%. The microstructure of post-test samples was observed with the scanning electron microscope(SEM), and the ablation rate of samples was also calculated. The result shows that when the ablation angle is 90°, 60°, 45°,the corresponding mass ablation rate for ablation experiment is 0.146,0.123,0.100g/s respectively. With the decrease of ablation angle, the mass ablation rate of samples is decreased gradually; while for the samples affected by particle erosion, the corresponding mass ablation rate is 0.452,0.455,0.432g/s and the line ablation rate is 1.863,1.323,0.843mm/s. The mass ablation rate is approximately unchanged and the line ablation rate is decreased. The smaller the ablation angle is, the more serious the thermalchemical ablation of gas, and thus increase the erosion area of axial fiber bundle under ablation condition and ablation gradient of radial fiber under ablation/erosion condition.

Ultra-low-grade magnetite could be used after magnetic separation, resulting in magnetic material being the major product. The content of useful and harmful components in magnetic materials are ideal for the washability evaluation of ultra-low-grade magnetite. However, they have received little attention so far. In this study, electromagnetic separation and Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) were used to determine the contents of useful and harmful compositions (TFe, V2O5, TiO2, P, Cu, Pb, Zn) in raw ore and magnetic material. When the component (V2O5, Cu, Pb, Zn) contents were far lower than the required contents of criterion, the contents of these elements after magnetic separation varied but did not affect the smelt and evaluation results. However, the contents of TFe, TiO2, and P changed obviously after magnetic separation. The TFe content increased from 14.23%-16.60% to 53.95%-69.86%, whereas the TiO2 content decreased from 4.43%-5.02% to 0.84%-1.83%. The P content decreased from 0.11%-0.30% to 0.027%-0.048%, which affected the smelt and evaluation results (in Table 2). The concentrations of TFe, TiO2, and P can be used to reflect the smelt selection of ultra-low-grade magnetite. The concentrate is easily obtained by low intensity magnetic separation and the content of TFe, P, Cu, Pb, Zn meets requirements. Attention should be paid to the evaluation of TiO2 in tailings since most TiO2 is concentrated in the tailings. In conclusion, this is a feasible method to evaluate the washability and define the objective elements of utilization by using electromagnetic separation and ICP-OES. This method can not only evaluate the smelt possibility of ultra-low-grade magnetite but can also determine the elements to be used, making it meaningful to the comprehensive utilization of ultra-low-grade magnetite.

A self-designed oxygen-kerosene ablation system was employed to study the ablation mechanism and performance of the carbon-carbon composites. Particle concentrations of the gas-solid two-phase ablation flow were 0, 1.37%, 2.22%, and 2.64% respectively. The microstructure of post-test samples was analysed through the scanning electron microscope (SEM), and the ablation rate was calculated. The influence principle of particle concentrations on the ablation rate of the carbon-carbon composites was studied, and the mechanism of ablation was analysed. Experiment results show that with no particles involved the mass ablation rate is 0.159g/s and the linear ablation rate is 0.175mm/s, while with particles introduced, the minimum mass ablation rate and linear ablation rate are 0.432g/s and 0.843mm/s respectively, with the increase of particle concentrations, the ablation rate becomes accelerated. Particle erosion makes the ablation of sample seriously intensified, and the ablation gradient of radial fiber on erosion surface is increased with the increase of particle concentrations as well.

With the rapid improvement of China’s socio-economic level, the importance of ecological environmental protection has become increasingly important. As a major factor affecting ecological environmental protection, carbon emissions have received high attention. At the same time, various tasks for energy conservation and emission reduction have entered a period of rapid development. In China’s construction industry, green buildings are the main measures for energy conservation and emission reduction. The use of green buildings to achieve water, material, and energy conservation can not only ensure environmental benefits, but also improve ecological benefits. In order to further improve the environmental benefits of green buildings from the perspective of carbon emissions, it is also necessary to conduct a specific analysis combining the development advantages and environmental benefits of green buildings.

X-ray Fluorescence Spectrometry (XRF) technique has been applied to the determination of non-metallic minerals such as gypsum. However, the method is limited due to the lack of certified reference materials and the high content of sulfur and easy volatilization loss of sulfur at high temperature. In order to fit the standard calibration curve, synthetic reference materials were prepared by using gypsum certified reference materials, high purity calcium sulfate and other national primary certified reference materials (soils, stream sediments, carbonate). A method for the determination of ten major and minor components (Si, Al, Fe, Ca, Mg, K, Na, Ti, S, Sr) by XRF was proposed. Dilution ratio and melting temperature were optimized and the matrix effect was corrected by a theoretical α coefficient. Results show that gypsum can be completely melted when the dilution ratio was 9:1 and the melting temperature was 1050℃. The detection limits of the method are 4-135 μg/g, and the precision (RSD, n=12) is less than 3.0%; analytical results of certified reference materials were in good agreement with certified values. The synthetic reference materials for the method expand the adaptability of the sample matrix. The lithium tetraborate-lithium metaborate flux in the melting process could be effectively combined with S, suppressing sulfur volatilization. The method is suitable for batch analysis of the gypsum samples with the sulfur content between 12.60% and 51.91%.

The content of magnetic iron is one of the basic analyses in ultra-low-grade magnetite exploration. In order to accurately determine the content of magnetic iron, quantitative separation of magnetic iron is very important. There is no standard method for the analysis of magnetic iron in iron ore, and the reproducibility of common artificial magnetic separation is poor due to the human factors and the difficulty of guaranteeing effective magnetic field intensity. A new magnetic separation device (electromagnetic separation device) was developed by using 50 mL burette, electromagnet and a three-phase asynchronous motor. Magnetic iron and nonmagnetic iron in ultra-low-grade magnetite was quantitatively separated by optimizing the working conditions. Determination of magnetic iron was proposed by combining the potassium bichromate titrimetric method with a magnetic separation technique. When the current was 2.5 A, the motion frequency of the magnetic tube was 40 times/min, and the time of magnetic separation was 5 min. The relative error was lower than 1.0% for the reference material. For the practical samples, the analysis results completed by the proposed method were in agreement with those determined by artificial magnetic separation with the RSD of the proposed method being lower than 1.0%, which was an improvement over the precision of artificial magnetic separation. For the new method, the magnetic field intensity was effectively controlled, the parameters for the separation of magnetic iron were quantized, and the measurement accuracy was improved for magnetic iron.