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This is an article in the field of metallurgical engineering, which proposed a new idea of mixing molten blast furnace slag with steel slag to achieve self-pulverization of steel slag, and systematically studied the influence mechanism of special components of CaF2 and CeO2 in blast furnace slag of Baotou Iron and Steel Company on the self-pulverization of steel slags. Using analytically pure CaO, SiO2, CaF2 and CeO2 as starting materials, pure C2S specimens were prepared with n ( CaO ) : n ( SiO2 ) = 2 : 1, then different mass fractions of CaF2 and CeO2 were added, respectively. The effect of CaF2 and CeO2 on the self-pulverization behavior of C2S was investigated by calcining the specimen at 1 450 °C for 1 h and cooling with the furnace. The results showed when CaF2 was incorporated into C2S and the content of CaF2 was less than 2.5%, it had little effect on the self-pulverization of C2S. However, when the content of CaF2 was more than 2.5%, the specimen had different degrees of agglomeration, which affected the self-pulverization of C2S. Considering that excessive CaF2 would affect the environment, the content of CaF2 should be controlled below 2.5%. When CeO2 incorporated into C2S and the content was 0.25%, C2S could still be completely self-pulverized, but when the CeO2 content was more than 0.5%, C2S no longer self-pulverized.Therefore, the CeO2 content must be less than 0.25 %, and the self-pulverization effect of C2S was relatively good.

Large quantity of observational data from ground and sounding meteorological observation data, ocean station observation data, ERA reanalysis data are used to count the sea fog process that occurred during April to July in Rizhao City from 1988 to 2019 altogether 32 years in this paper. The synoptic characteristics of the sea fog and their formation mechanism are statistically analyzed, and furthermore the main meteorological elements affecting the formation of sea fog in Rizhao area and their combined effects are put forward. The results indicate that sea fog occur in Rizhao area is most likely under the control of several weather conditions, such as the west of transition high to sea, the Pacific subtropical high ridge or the front of low or trough of the eastern China in spring and summer. Under the control of these synoptic characteristics, the direction and speed of wind, dew-point temperature, atmospheric temperature, SST, stratification stability of these hydrometeorological elements play an important role in the formation of sea fog. On these basis, the method of discriminance analysis is used to establish of discriminant equation for sea fog forecast. Through the forecast testing, the statistical forecasting method of sea fog has a great application, the forecast accuracy is between 88% and 94%. It can be used for short-term forecast of sea fog characteristics in Rizhao City, providing services for industry, agriculture, fishery production, sea and land transportation.

Perilla frutescens (L.) Britt. is one of the edible and medicinal plants. The purpose of this study was to compare the flavonoids and polyphenols extracted from different varieties of P. frutescens leaves ('Korean green PF1', 'Chinese PF2', 'Korean purple PF3', 'Korean bicolor PF4', 'Chinese bicolor PF5'), and to explore their antioxidant activities in vitro. Optimization of extraction process of flavonoids and polyphenols from P. frutescens leaves was studied by single factor tests and orthogonal test. The results showed that the optimum parameters were ethanol concentration 75%, solid-liquid ratio 1:80 g/mL, extraction time 2 h, extraction temperature 70 ℃. Under these conditions, the extraction amount of flavonoids and polyphenols was the highest, which were (16.82±0.60) mg/g and (80.42±2.66) mg/g, respectively. Among different varieties of P. frutescens leaves, PF3 had the highest content of polyphenols (17.77±0.29) mg/g, PF5 had the highest content of flavonoids (80.42±2.66) mg/g. The results of antioxidant activity showed that the leaves of different varieties of P. frutescens had good antioxidant activity. Among them, the ABTS+ free radical scavenging rate (IC50 150.31±2.46 μg/mL), DPPH free radical scavenging ability (IC50 88.04±3.61 μg/mL) and total reducing power of PF5 were the strongest (P

The Longfengshan area is an important hydrocarbon enrichment area in the Changling Fault Depression. Most of the oil and gas are distributed near the fault zone. It is of great significance to discuss the relationship between faults and hydrocarbon migration and accumulation. Combined with seismic, logging, core, microscopic thin sections, fluid inclusion observations and temperature measurement data, the relationship between section morphology, fault activity characteristics and hydrocarbon migration and accumulation is comprehensively analyzed on the basis of fault static characteristics and fault zone structure identification. The results show that a large number of fractures are developed in the fault-induced fracture zone, which can effectively improve the physical properties of volcanic rocks, and the fault can be used as the dominant migration channel for hydrocarbons. The "convergent" section shape of the grade Ⅰ fault controls the main enrichment location of hydrocarbons. The fault activity matches well with the first stage of reservoir formation, and faults can be used as a dominant channel for transporting hydrocarbons. In the later stage, the fracture of the fault zone is filled with quartz and calcite, and the fault zone mainly plays a sealing role in the volcanic oil and gas reservoirs.

【Objective】The study was carried out to investigate the prevalence of porcine circovirus Type 2 (PCV2) in pigs and cattle in Yunnan Province, and to identify the genetic variation and molecular evolution trend of PCV2 strains in Yunnan Province.【Method】PCR method was used to detect the etiology of PCV2 in 783 blood and manure samples of pigs and cattle from 11 regions of Yunnan Province. The whole genome amplification, cloning and sequencing of 6 PCV2 positive samples were carried out. The whole gene and ORF2 amino acid sequences were compared and analyzed by DNAStar software, and the genetic evolution tree was drawn by MEGA software.【Result】The positive rate of PCV2 of detected samples was 48.73%. A total of 6 strain PCV2 genome sequences were measured, of which 5 strain were 1 767 bp and 1 strain was 1 768 bp. The genetic development analysis showed that there were 2 strains of PCV2a subtype, 2 strains of PCV2b subtype and 2 strains of PCV2d subtype. The homology of 6 strains PCV2 was 94.6%-99.9%, and the homology with 20 national reference strains in GenBank database was 91.4 %-99.8 %. The ORF2 of 6 strains PCV2 had their typical amino acid sites. The amino acid site of PCV2a strain was mutated to be consistent with PCV2 (b/d) at the 80th (V80L) amino acid site, and the amino acid site of PCV2b strain was mutated to be consistent with PCV2d at the 59th (R59K), 63rd (K63R), 190th (A190T) and other amino acid sites.【Conclusion】PCV2 commonly exists in pigs in Yunnan, and the three gene subtypes of PCV2a, PCV2b and PCV2d coexist, and PCV2 (a/b) has a tendency to mutate to PCV2d. Holstein cows have not been infected with PCV2.

Taste perception is an important factor in determining people's food intake. Understanding the relationship between taste sensitivity and food consumption behavior is one of the most innovative strategies for solving health problems caused by diet, and measuring the taste sensitivity of human subjects is the key to establish this relationship. In this paper, from the aspects of working principle, operation process and application of taste sensitivity determination, the methods of measuring human taste sensitivity at home and abroad are summarized, including psychophysical method, biopotential method, bacterial papilla counting method and genotyping method. Psychophysical measurement method is simple to operate and easy to implement, but subjective and error are large; biopotential measurement method reduces subjective errors, but the subjects need to remain relatively static during the measurement process, otherwise it will affect the stability of the electrode; fungal papilla counting method and genotyping method need to be carried out in conjunction with other methods. In addition, the genotyping method requires high technical content and cost. Through the analysis and evaluation of the above methods, it provides a theoretical basis and guidance for selecting different taste sensitivity determination methods.

An in-situ measurement device combining contact probe and capacitive displacement sensor is developed. An aspherical measurement and compensation machining software is also developed. The single point diamond ultra precision cutting experiments for C3604 brass spherical and aspherical surface are carried out. The in-situ measurement and compensation machining experiments are also carried out. After compensation machining, the spherical surface form accuracy PV reaches 231.4 nm, and the aspheric surface form accuracy PV reaches 206.3 nm. Compared with the off-line measurement results, the difference between the results is 3.0 nm, 7.0 nm respectively, the measuring accuracy of the in-situ measurement system and the validity of compensation machining are verified.

The stress state of joints is the key to the mechanical performance of the space structure. In this paper the constant amplitude fatigue performance of the pin in space structure was investigated. The fatigue numerical simulation of 32 theoretical models with 5 factors was carried out on the basis of similar numerical models and nCode Designlife analysis software. The S-N curve was obtained and the fatigue life calculation formula was established. The analysis results indicate that: Under the symmetrical cyclic loading (R=-1), the hot spot stress of the pin locates at the contact surface of the pin with the interface of the outer and inter ear plates, and the nominal allowable stress amplitude corresponding to 2×106 cycles is 94.42 MPa. The constant amplitude fatigue performance of the pin is negatively correlated with the three parameters, the pin hole clearance, the thickness of the ear plate, and the distance between the ear plates, while positively correlated with the pin diameter and the yield strength of the pin material. The ranking of the sensitivity of the factors affecting the constant amplitude fatigue performance of the pin is: the material of pin→the clearance of pin hole→the space between ear plates→the diameter of pin→the thickness of ear plate.

To improve the preoperative positioning efficiency and terminal operability of the minimally invasive surgical robot，a new multi-slave manipulator system of minimally invasive surgical robot is designed，which includes the preoperative positioning mechanism and the remote-center mechanism. Three surgical instrument arms and one endoscopic arm can be installed on the base. The fixed point of the end can be realized through the parallelogram mechanism in the remote-center mechanism，and the workspace can be increased by adding redundant DOF on the basis of the pitch，roll，and translation DOFs. To facilitate the doctor to adjust the height of the remote-center mechanism before the operation，the gravity compensation joint of the preoperative positioning mechanism is compensated for the gravity of the remote-center mechanism by the constant force spring. Based on the structural design of the multi-slave manipulator system，the forward kinematic analyses of the active part and the passive part are carried out. Since the preoperative positioning mechanism is used for preoperative positioning on the active part and each joint of the passive part will be locked during the operation，the inverse kinematics and the workspace of the active part are only analyzed. By comparing the motion trajectory simulated by SolidWorks with the motion trajectory of the end of the robot obtained by Matlab，the rationality of the structure of the multi-slave manipulator system and the correctness of the kinematics can be verified.

The Baode Coalbed Methane Field is located in the northern section of Jinxi Flex Belt on the eastern edge of Ordos Basin. It is a typical coal seam gas field of middle and low ranks. In 2011, the gas field proved 18.363×109 m3 of proven geological reserves and 9.182×109 m3 of technically recoverable reserves. The reserve area has been developed on a large scale for 6 years. The reserve calculation parameters have changed significantly, so it is necessary to reassess the utilization and availability of reserves. In September 2018, we recalculated geological reserves using the volume method and dynamic information by combining reserve specification with the output mechanism and development characteristics of coalbed methane. The production decline method and analogy method were used to recalibrate the recovery rate. Then, the proved reserves submitted in 2011 were recalculated. The proved reserves of coalbed methane increased by 2.986×109 m3 after compounding. The recovery calibration result is 52%, up 2% from 2011. The recoverable reserves of calibration technology were 11.094×109 m3, with an increase of 1.912×109 m3 over 2011. Reserve recalculation focuses on the changes in calculation parameters. In the calculation of technical recoverable reserves and the determination of recovery rate, it is necessary to carry out classification and calculation according to geological conditions in the developed area.

A visualization experimental method of foam flooding was developed by combining nuclear magnetic resonance (NMR) and traditional core flooding method. On this basis, a new method to evaluate the dynamic stability of foam in the core during displacement process was established. Using this method, the displacement characteristics and dynamic stability of foam of S-2 (the main component is sodium lauryl sulfate) and S-NP-2 (the main components are sodium lauryl sulfate and silica nanoparticles) in two different displacement modes, i.e. direct foam flooding and foam flooding after water flooding, were studied. The results show that the NMR images and the T2 (transverse relaxation time) spectrum reflected the displacement characteristics. The flooding efficiency of S-2 and S-NP-2 after water flooding was increased by 18.05% and 25.68% and reached 63.72% and 67.50% respectively at last, higher than direct foam flooding. The same foam system had better stability in foam flooding after water flooding than in direct foam flooding, and foam S-NP-2 is more stable than foam S-2 under the same displacement mode. Key words: foam flooding, flooding experiment, flooding efficiency, nuclear magnetic resonance (NMR), foam stability, evaluation method

The distribution and migration characteristics of weak gel in the core were observed by combining nuclear magnetic resonance (NMR) imaging technology with the core displacement experiment, and the oil displacement features of different polymer-weak gel combinations were examined with visualization experiments. Three combination patterns of polymer and weak gel were designed: waterflooding + polymer flooding (pattern 1), waterflooding + polymer flooding + weak gel flooding (pattern 2), and waterflooding + weak gel flooding + polymer flooding (pattern 3). The pressure variations, T2 spectra, nuclear magnetic resonance images, oil displacement efficiencies under the different patterns were analyzed. The results show that the nuclear magnetic images can not only provide the direct information of weak gel distribution and migration characteristics inside the core, but also reflect the distribution characteristics of remaining oil; the T2 spectrum characteristics indicate that both polymer and weak gel have the function of profile control and oil displacement, and the pattern 2 has the best profile control effect; of the three patterns, pattern 2 has the highest oil displacement efficiency of 78.84%, which is 18.33% higher than the displacement efficiency of water flooding in the initial stage. Key words: weak gel, polymer, nuclear magnetic resonance (NMR), visualization displacement experiment, oil displacement efficiency

Objective: To investigate the clinical and biological characteristics of familial platelet disorder (FPD) with germline Runt-related transcription factor (RUNX) 1 mutations. Methods: Patients diagnosed with myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) with RUNX1 mutations from February 2016 to December 2021 in Wuhan No.1 Hospital underwent pedigree analysis and were screened for gene mutations (somatic and germline). Patients diagnosed with FPD with germline RUNX1 mutations were enrolled and evaluated in terms of clinical characteristics and biological evolution. Bioinformatics analysis was used to assess the pathogenicity of mutations and to analyze the effect of mutated genes on the function of the corresponding protein. Results: Germline RUNX1 mutations were detected in three out of 34 patients suffering from MDS/AML who had RUNX1 mutations. A pedigree of FPD with RUNX1 (RUNX1-FPD) c.562A>C and RUNX1 c.1415T>C mutations was diagnosed, and the mutations were of patrilineal origin. Bioinformatics analysis indicated that the locus at positions 188 and 472 in the AML-1G type of RUNX1 was highly conserved across different species, and that variations might influence functions of the proteins. The mutations were evaluated to be highly pathogenic. Of the nine cases with germline RUNX1 mutations: two patients died due AML progression; one case with AML survived without leukemia after transplantation of hemopoietic stem cells; four patients showed mild-to-moderate thrombocytopenia; two cases had no thrombocytopenia. During the disease course of the proband and her son, mutations in RUNX1, NRAS and/or CEBPA and KIT appeared in succession, and expression of cluster of differentiation-7 on tumor cells was enhanced gradually. None of the gene mutations correlated with the tumor were detected in the four cases not suffering from MDS/AML, and they survived until the end of follow-up. Conclusions: RUNX1-FPD was rare. The mutations c.562A>C and c.1415T>C of RUNX1 could be the disease-causing genes for the family with RUNX1-FPD, and these mutations could promote malignant transformation. Biological monitoring should be carried out regularly to aid early intervention for family members with RUNX1-FPD.

Non-point source pollution risk assessment and zonation research are of great significance for the eco-environmental protection and optimization of land use structure. We identified the "source" and "sink" landscape using the "source-sink" landscape pattern theory based on the two phases of land use data in the lower reaches of Zijiang River in 2010 and 2018. We comprehensively considered the non-point source pollution occurrence and migration factors, and used location-weighted landscape contrast index (LCI) and non-point source pollution load index (NPPRI) to analyze non-point source pollution risk spatio-temporal characteristics in the study area. Zonation on non-point source pollution in the lower reaches of Zijiang River was studied by identifying the key factors of non-point source pollution risk. The results showed that the overall risk of non-point source pollution was relatively low. The sub-basin with "sink" landscape was the main type, accounting for 61.2%. Non-point source pollution risk was low in the southwest and was high along the banks of Zhixi River, Taohua River and main stream of Zijiang River, as well as plain in the northeast of the lower Zijiang River. The risk of non-point source pollution from 2010 to 2018 showed an increasing trend. The changes in landscape pattern, especially the expansion of rural settlement, arable land and the shrinkage of forest land had positive and negative responses to the risk of non-point source pollution, respectively. LCI, slope, and distance were the key factors affecting the change of the risk index of non-point source pollution. The lower reaches of the Zijiang River could be divided into four control regions: pollution treatment area near river, low slope pollution control area, ecological restoration-risk prevention and control area, and ecological priority protection area.

Objective: To understand the professional theory, prevention and control practice, experimental diagnosis and other technical skills of parasitic diseases among technicians of all levels of disease control and prevention institutions, so as to provide the evidence for strengthening the capacity building of Chinese professional personnel., Methods: According to the method of recommendation at all levels, the subjects from disease control and prevention institutions at province, prefecture or county levels were chosen to assess the theory of parasitic diseases and test operation skills by using the method of answering the questions together with on-site operations in China. A database was built consisting of subjects' basic information and assessment scores. By using the method of hierarchical classification, the scores by gender, age, professional title, institutions and places of participants were analyzed., Results: A total of 124 professions in prevention and treatment of parasitic diseases in 31 provinces (cities and regions) were evaluated in China. The average total score of all the subjects was 125.0 ± 35.2, with a passing rate of 54.8%. The average scores of male subjects and female subjects were 120.8 ± 34.2 and 126.6 ± 35.4 respectively; the average scores of the subjects aged under 30 years, between 30 and 40 years, and above 40 years were 125.6 ± 33.6, 124.9 ± 35.8, and 119.3 ± 45.9 respectively; the average scores of persons with junior, intermediate and senior professional titles were 119.8 ± 35.8, 136.0 ± 32.5 and 127.1 ± 40.9 respectively. The average theoretical assessment score of all the subjects was 67.4 ± 15.6, with a passing rate of 68.5%. The average practical skill assessment score of all the subjects was 57.6 ± 21.8, with a passing rate of 46.0%. The average detection rates of Plasmodium falciparum , P. vivax , P. ovale and P. malariae in endemic and non-endemic areas were 64.1%, 72.8%, 57.0%, 58.3% and 35.9%, 46.9%, 33.3%, 43.8%, respectively. The detection ability of professionals in endemic areas was significantly higher than that in non-endemic areas ( χ 2 = 767.10, 462.12, 134.97 and 360.80, respectively, all P < 0.01). The total detection rate of schistosome eggs was 48.7%, and the detection rates of schistosome eggs were 67.4% and 36.8% in endemic and non-endemic areas, respectively. The detection ability of professionals in endemic areas was significantly higher than that in non-endemic areas ( χ 2 = 817.74, P < 0.01). The detection rates of Ascaris lumbricoides , Trichuris trichiura , and Enterobius vermicularis were 85.7%, 78.6%, 91.7%, and 61.8%, 23.5% and 74.4% in the technicians in southern region and northern region of China, showing significant differences ( χ 2 = 622.58, 301.70 and 588.71, respectively, all P < 0.01)., Conclusions: The overall results of the subjects are good, but the technical operation capability of them is relatively low. Therefore, the specific training based on daily work needs should be enhanced. In addition, we should attach importance to talent cultivation and technical reserve, and strengthen the construction of the team, so as to meet the needs of the prevention and control of parasitic diseases.

Objective: To understand the risk factors of cystic echinococcosis in Tibetan population, so as to provide the reference for development of prevention and control strategies., Methods: Four cystic echinococcosis highly-prevalent townships were selected from Naqu County of Tibet and Shiqu County of Sichuan Province, which had similar environmental and altitude conditions, from August to September, 2017. Applying the 1∶1 case-control study, a household survey was conducted to investigate the risk factors of echinococcosis in humans., Results: A total of 378 residents were investigated, of which the numbers of cases and non-cases were both 189. The univariate analysis showed that the years of keeping dogs ( OR = 1.032, P < 0.05), the number of keeping dogs ( OR = 1.260, P < 0.05), the way of raising dogs ( OR = 1.434, P < 0.05), feeding with raw viscera ( OR = 1.531, P < 0.05), and there being stray dogs around ( OR = 1.946, P < 0.05) were the risk factors of echinococcosis. As a result of the multivariate logistic regression analysis, only three risk factors, feeding with raw viscera, there being stray dogs around, and drinking water resource, were included in the regression model., Conclusions: Feeding with raw viscera, there being stray dogs around, and drinking water resource are the risk factors of echinococcosis in humans.

Objective: To report the integrated progress of the hydatid disease information management system, and to provide the reference for further system improvements by analysis of results on simulation test feedback., Methods: The work of institutional code matching by collecting fundamental and integrated information of the system in epidemic areas of hydatid disease was carried out, and professional control agencies were selected to carry out the simulation test., Results: The results of agencies code matching at stage indicated the average completion rate was 94.30% on administrative agencies, 69.94% on registered professional agencies and 56.40% on professional institutions matching related to hydatid disease prevention and control implements in seven provinces (autonomous regions) and Xinjiang Production and Construction Corps. Meanwhile, the response rate of open-ended proposals was 93.33% on fifteen feedbacks, and the statistics showed 21.43% believed the system was low fluency, 64.29% considered the system was inconvenience for data inputs and 42.86% considered it would be improved on system statistics functions, of which 27.78% were provincial users, 22.22% were the city users and 50.00% were the county users., Conclusions: The hydatid disease prevention information management system meets the fundamental needs of the majority agencies in hyperendemic areas of echinococcosis, it needs to develop the further test with more agencies joining after the work of the institutional code matching completion and the system service improvement in the next stage.

Objective: To evaluate the risk factors associated with pathogenesis of cerebral palsy (CP) in young children., Methods: A cross-sectional survey on the prevalence of CP was conducted in young children aged one to six years in Leshan area, Sichuan Province. Cluster sampling and a 1:2 case-control design were used to investigate the risk factors for pathogenesis of CP., Results: Totally, 148,723 children were surveyed, in which 308 (2.07 per thousand ) were diagnosed as CP. Low birth weight, twins and premature birth were associated with significantly increased prevalence of CP, 16.32, 4.16 and 22.21 times as that in normal birth weight, single birth and full-term birth, respectively. Simple factor analysis showed varied factors involved in pathogenesis of CP. The multivariate analysis revealed that delivery at home, low Apgar score in five minutes, illness during the first month of life, maternal "cold" with fever in their early gestation, low protein (meat and egg) intake during pregnancy and lower education level of mother were risk factors for CP., Conclusions: Prevalence and clinical features of CP in Leshan was comparable to those in the developed countries. Relevant risk factors could be seen primarily in gestational and perinatal periods, which might involve in mothers, children, environment and heredity, etc. To attach more importance in gestational and perinatal care for mothers and babies will be crucial measures to reduce occurrence of CP in young children.

The rhizomes and roots of Curcuma are commonly used as Traditional Chinese Drugs. In this paper, a new species of Genus Curcuma from Sichuan, viz. Curcuma chuanyujin is reported, it is similar to C. aromatica, but differs from the dispersion of downs and the colour of bracts.

In this paper the relationship of Tibetan Huanglian and Yunnan Huanglian with Coptis teeta has been studied. The distribution and taxonomic features of Tibetan Huanglian are just the same as Coptis teeta, but quite different from Yunnan Huanglian. The results reveal that Tibetan Huanglian and Yunnan Huanglian are different in botanical origin.

The rhizomes of Coptis, known as Huang-Lian, are commonly used as traditional Chinese drugs. Two new species, viz., Coptis linearisepala, C. gulinensis and a new variety, viz., C. chinensis var. unguiculata are reported and the descriptions of the new species and new variety are presented in the present paper.

Quantitative determination of berberine, coptisine, palmatine, jatrorrhizine and epiberberine in Coptis chinensis, C. deltoidea, C. teetoides, C. omeiensis, C. chinensis var. brevisepala, C. linearisepala, C. gulinensis, C. chinensis var. unguiculata, C. teeta and 5 different samples of C. chinensis was made by thin layer chromatography-densitometry.