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The iron and steel industry is an important basic industry of national economy，which uses a large amount of water，involves a long production process，and discharges a large number of pollutants. In order to strengthen the water pollutant discharge management of iron and steel industry，the United States，Germany，the European Union and other countries（regions） and the World Bank have all formulated water pollutant discharge standards，and each standard has its own characteristics. This paper sorted out Chinese and foreign water pollutant discharge standards for iron and steel industry，compared and studied the applicable scope，pollutant items，discharge limits，determination requirements of exceeding limit and other major technical contents. Finally，in order to improve Chinese discharge standards for iron and steel industry，relevant work suggestions were put forward.

In order to better understand the corrosion risk of single pole operation of high-voltage direct current (HVDC) grounding electrodes on pipelines, a comprehensive review of corrosion monitoring technologies for buried pipelines over recent decades was conducted in this paper; the principles of various corrosion monitoring techniques were introduced, and the application status of different corrosion monitoring technologies in the context of HVDC interference with buried pipelines was summarized; the advantages and disadvantages of four rapid corrosion measurement methods, namely the field burial method, intelligent pile monitoring method, electrochemical reduction (ER) corrosion rate probe method and laboratory simulation experiments, in evaluating the corrosion rate of buried pipelines under HVDC interference were mainly analyzed. Based on this analysis, recommendations for the application of various corrosion monitoring techniques in the field of HVDC interference with buried pipelines were proposed. Additionally, new directions in monitoring technology for corrosion rate of buried pipelines under HVDC interference were explored, providing references for relevant researchers and engineers.

An experimental study is conducted to investigate the surface integrity in spindle barrel finishing of 14CrMnSiNi2MoA aviation cylindrical spur gears. The surface morphology, residual stress, microhardness, microstructure of aviation gears before and after barrel finishing are systematically studied by professional instruments. The results indicate that the gear surface integrity can be significantly improved by spindle barrel finishing. The surface roughness of the gear reduces to less than 0.2 μm and the average residual compressive stress of the gear surface increases by about 45%. The hardness of the gear surface also increases. The results of surface roughness and residual stress distribution before and after barrel finishing reveal that the increase of residual compressive stress and decrease of roughness of the gear surface increase gradually from the root to the top of the gear, which provides a basis for the setting and designing of processing parameters in barrel finishing.

In order to study the influence of different operating modes on the dynamic response and stability of offshore wind turbines under turbulent wind and earthquake, DTU 10 MW offshore single-pile wind turbine was used as the research object. The p-y curve was used to describe the interaction between the pile foundation and the subsea soil. Based on the finite element software ANSYS, the finite element model of the wind turbine was established and the structure modal, dynamics and buckling calculation of the wind turbine were carried out. The results show that the vibration mode of the tower is dominated by torsional and bending vibration. Its first natural frequency is within the ideal design range and the rotation of the wind wheel will not cause its resonance. Turbulent wind has the most significant influence on the displacement of tower top and earthquake has much greater influence on the lateral displacement of tower top than the turbulent wind. After the earthquake, the equivalent stress and strain energy response of the tower have surged. The emergency shut-down can effectively reduce the peak of the tower top displacement, the tower equivalent stress and the tower strain energy response and reduce the risk of structural damage and plastic deformation. Under the action of turbulent wind and earthquake, lateral buckling failure will occur in the middle and upper part of the leeward surface of the tower. The emergency shut-down can effectively improve its buckling resistance and the maximum increase of critical buckling load is nearly 27.11%.

The non-linear motion characteristics of the large-scale floating wind turbine have been significantly enhanced. For this reason, the DTU 10 MW wind turbine was used as the research object, and the NAUTILUS semi-submersible platform floating wind turbine model was established, and the tuned mass damper（TMD） was installed in the nacelle Optimize TMD parameters through multi-island genetic algorithm, study the motion response characteristics of floating wind turbines without TMD control, TMD control（unoptimized） and optimized TMD control, and based on chaos theory, adopt phase space reconstruction and maximum Lyapunov exponent method from qualitative and quantitative analysis of the nonlinear characteristics of floating wind turbine motion response. The results show that under TMD control and optimized TMD control, the forward to after displacement response of the floating wind turbine tower top is significantly reduced, but the side to side displacement response is relatively small; the peak forward to after acceleration response of the tower is significantly reduced in the range of 30 m～90 m. The peak value of side to side acceleration response decreases in the range of 10 m～30 m. Compared with the non-TMD control, under the optimized TMD control, the chaotic characteristics of the floating wind turbine’s motion response are weakened, and the maximum Lyapunov exponents are all reduced, indicating that the optimized TMD can reduce the nonlinear characteristics of its motion response.

Taking the DTU 10 MW wind turbine as the research object, the OO-Star semi-submersible platform floating wind turbine model is established, based on the blade element momentum theory and the radiation/diffraction theory to solve the wind load and wave load respectively, and the dynamic response of floating wind turbines under different environmental load directions is simulated, and the impact of different environmental load incident angles on its response characteristics is compared and analyzed. The results show that the incident angle of turbulent wind has a greater influence on the response of floating wind turbines to surge, pitch and yaw, while the incident angle of wave has a great influence on the sway and roll response. The heave response hardly changes with the turbulent wind and wave incident angle. As the incident angle of turbulent wind increases, the average power of floating wind turbines drops sharply, while the incident angle of waves has almost no effect on its average power. In addition, in the mooring system, the mooring tension of No.1 increases gradually with the increase of the incident angle of turbulent wind and wave, while that of No.2 mooring decreases gradually, while that of No.3 mooring increases first and then decreases with the increase of incident angle of turbulent wind, and increases gradually with the increase of incident angle of wave.

When TMD is used in the nacelle or tower of the floating wind turbine, its stability can be improved, but the fatigue load of the tower base is increased. In order to solve this problem, the ITI Barge platform is taken as the research object, TMD is arranged inside the platform for vibration damping control, and the dynamic model of the floating wind turbine is established to study the change law of the front-after and side-side displacement of the tower top with the TMD mass, damping and installation position. The multi-island genetic algorithm is used to obtain the optimal TMD parameters, and the effects of without TMD control, nacelle TMD control and platform TMD control on the dynamic response characteristics of floating wind turbine are compared and analyzed. The results show that the front-after and side-side displacements of the tower top change significantly with platform TMD parameters. When mass and damping of the platform TMD at the same location are large, the front-after and side-side displacements of the tower top decrease significantly. When mass and damping of the platform TMD remain unchanged, the front-after and side-side displacements of the tower top decrease gradually with the increase of the TMD location. Under the action of wind and wave, the effect of TMD on the dynamic response control of floating wind turbines under wind load is more obvious, but the control effect of each part is different. The side-side displacement of the tower top, the platform roll angle and the tower base roll bending moment control effect are the most significant. In addition, compared with the nacelle TMD control, the stability of the floating wind turbine is better when controlled by the platform TMD.

In order to study the structural characteristics of different types of bend-twist coupling blades, the NREL 5 MW wind turbine blade was used as the research object, combined with composite material laying design to establish finite element models of different BTC blades, the aerodynamic load of the blades were solved by CFD method. The modal, strength and buckling of the blades were calculated and the effects of different coupling regions and coupling angles on the structural characteristics of the blades were analyzed. The results show that the natural frequencies of BTC blades are mostly lower than that of the traditional blades. The skin-coupled blades have the smallest change and the fully coupled blades have the greatest influence; the BTC blades can reduce the internal von Mises stress and strain peak value and improve the fatigue life of the blade. The skin-coupled blades have the largest reduction and the spar cap-coupled blades have the smallest reduction. The skin-coupled blades have the best load reduction effect when θ=20°; the shear stress of the BTC blades are mostly higher than that of the traditional blades, only the maximum shear stress of the skin-coupled blades θ=20° is lower than that of traditional blades; the bend-twist coupling characteristics of the blades have a certain impact on its stability. The critical buckling load of spar cap-coupled blades have a large decrease, while other BTC blades have a slight increase, and the amount of the first-order buckling deformation is lower than traditional blades.

Objective To study the clinical distribution and detection of the efflux pump gene in multiple drug-resistant acinetobacter baumannii. Methods The clinical distribution of 96 strains of multiple drug-resistant acinetobacter baumannii was analyzed. K-B method was used to detect 96 strains of multi resistant bauman resisted to 15 kinds of antibiotics. PCR amplification was used to detect the efflux pump gene. Results Ninety-six strains of multiple drug-resistant acinetobacter baumannii mainly distributed in intensive care unit (ICU, 54.2%) and respiratory department (18.8%). The drug resistance rates to quinolone, cephalosporins, amino glucoside, tetracycline were above 70%. The 52 strains of multiple drug -resistant acinetobacter baumannii detected in ICU included 18 strains of adeB (34.62%), 16 strains of adeR (30.77%), 18 strains of adeS (34.62%), 18 strains of adeJ (34.62%), 0 strain of adeE and18 strains of adeM (34.62%). The18 strains of multiple drug-resistant acinetobacter baumannii detected in respiratory department included 9 strains of adeB, 8 strains of adeR, 8 strains of adeS, 8 strains of adeJ, 0 strain of adeE and 8 strains of adeM. Conclusion Efflux pump genes are important factors for multiple drug-resistant acinetobacter baumannii distributed in ICU and respiratory department. [ABSTRACT FROM AUTHOR]

Through the analysis on the principle of electromagnetic radiation interference (EMI) of wiper motor, the issue is simplified into the radiation interference of its wiring harness, and then a vehicle model for the electromagnetic radiation of wiper motor is established. The wiring harness is simulated as discretized transmission line model with lumped parameters, to calculate its current distribution as the exciting source of wiring harness and its radiation characteristics is investigated by using finite integration technique. The results show that the electromagnetic interference of wiper motor has obvious influences on the antenna and radio in vehicle. The results of simulation on the corresponding EMI suppression measures indicate that for suppressing the radiation intensity of harness, the reduction in contact resistance of wiper motor has no apparent effects, while the common-mode/differential-mode capacitor filtering have better effects, in particular the former, and adding series inductance on the base of common-mode capacitor filtering to form a low-pass filter can further reduce harness radiation. With this result as reference, a modification for EMI is conducted on the wipe motor of a real car, whose radiation exceeds the standard limit, by adding low-pass filter, leading to significant reduction in EMI and hence meeting the requirements of regulation. [ABSTRACT FROM AUTHOR]

Objective: To investigate the surgical outcomes and safety of the follower arm endoscope holder in assisting type Ⅰ tympanoplasty. Methods: The clinical data of 16 patients who underwent type Ⅰ tympanoplasty at the Department of Otorhinolaryngology, Peking Union Medical College Hospital, from November 2022 to September 2023 were retrospectively analyzed, among which 8 cases were operated by traditional otoscopy and 8 cases were operated by supported endoscopy.The surgical procedure was analyzed and the completion of supported endoscopic operation was observed, while the duration of the operation, the time consumed by the main steps, the frequency of wiping the lenses, the perioperative complications, and the improvement of the postoperative hearing were recorded and statistically analyzed. Results: Supporting endoscopic technology achieved real-time suction of bleeding, simultaneous traction and separation of tissues, precise removal of calcified spots on the inner side of the eardrum, trimming of the external auditory canal flap, stable separation of the handle of the malleus and the eardrum, and tensioned repositioning of the skin-cartilage flap. The average duration of surgery, time for external auditory canal flap preparation, and time for repositioning the skin-cartilage flap were reduced in the supporting endoscopic surgery group compared to the control group. The average lens wiping frequency was significantly lower in the supporting endoscopic surgery group compared to the control group. There was no statistically significant difference in postoperative hearing improvement between the two groups, and no infections or the need for secondary surgery due to eardrum re-perforation occurred postoperatively. Conclusion: Supported endoscopy technology realizes the need for endoscopic two-handed operation and convenient switching between one and two hands, accomplishes many operations that cannot be done by traditional endoscopic surgery, solves the problems of previous intraoperative one-handed operation and image instability, shortens the average operation time compared with traditional otoscopic surgery, and decreases the frequency of intraoperative wiping of the lens significantly compared with traditional otoscopic surgery, which is potentially worthwhile in terms of shortening the learning curve., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Objective: To explore the genetic basis for a Fra(16)(q22)/FRA16B fragile site in a female with secondary infertility., Methods: The 28-year-old patient was admitted to Chengdu Women's and Children's Central Hospital on October 5, 2021 due to secondary infertility. Peripheral blood sample was collected for G-banded karyotyping analysis, single nucleotide polymorphism array (SNP-array), quantitative fluorescent polymerase chain reaction (QF-PCR) and fluorescence in situ hybridization (FISH) assays., Results: The patient was found to harbor 5 mosaic karyotypes involving chromosome 16 in a total of 126 cells, which yielded a karyotype of mos 46,XX,Fra(16)(q22)[42]/46,XX,del(16)(q22)[4]/47,XX,del(16),+chtb(16)(q22-qter)[4]/46,XX,tr(16)(q22)[2]/46,XX[71]. No obvious abnormality was found by SNP-array, QF-PCR and FISH analysis., Conclusion: A female patient with FRA16B was identified by genetic testing. Above finding has enabled genetic counseling of this patient.

Objective: To explore the cause of inconsistent genotypes for an α-thalassemia carrier by using two commercial genotyping kits., Methods: GAP-PCR and PCR-reverse dot blotting (PCR-RDB) were employed to determine the genotype of the carrier, while Sanger sequencing was used to verify the results., Results: Sequencing analysis demonstrated that the subject has carried a α1 globin gene with a 3.7 kb heterozygous deletion. In addition, two novel mutations, IVS-II-55(T>G) and IVS-II-119(G>TCGGCCC), were found in intron 2 of α2 globin gene., Conclusion: The two mutations located in the binding regions of PCR primers have caused failure of PCR amplification and misreading of the genotype. Combination of clinical and hematological phenotypes is indispensible to infer the genotype of carriers for accurate diagnosis.

Laryngopharyngeal reflux (LPR) is gaining extensive attention in recent years because of the high incidence. But because of the complex symptoms and signs, there exist no diagnostic consensus. In this paper, the available objective diagnostic methods so far are reviewed, in the purpose of discussing the approach of objective and accurate diagnosis of LPR.

Objective: To observe the effect of acetazolamide (AZ) on the expressions of aquaporin 1 (AQP1) and AQP3 in fibroblast-like synoviocytes of rheumatoid arthritis (RAFLSs) and explore the roles of AQP1 and AQP3 in the development of rheumatoid arthritis (RA)., Methods: The study included 12 RA with knee hydrarthrosis and 10 osteoarthritis (OA) with knee hydrarthrosis and collected their synovia. From the synovia, FLSs were separated and cultured in vitro. RAFLSs were treated with different concentrations of acetazolamide (10(-4), 10(-6), 10(-8) mol/L) for different time (24, 48, 72 hours). The expressions of AQP1 mRNA and AQP3 mRNA in RAFLSs and OAFLSs were measured by RT-PCR; the expression of AQP1 protein was detected by immunofluorescence in RAFLSs and OAFLSs treated with the same concentration of acetazolamide (10(-4) mol/L) for different time (24, 48, 72 hours)., Results: AQP1 mRNA and AQP3 mRNA were both expressed in RAFLSs. The level of AQP1 mRNA in RAFLSs was significantly higher than that in OAFLSs (P<0.05). Different concentrations of acetazolamide (10(-4), 10(-6), 10(-8) mol/L) were able to significantly decrease the expression level of AQP1 mRNA in RAFLSs (P<0.05) in a time- and dose-dependent manner. There was no significant difference in transcription level of AQP3 mRNA between RAFLSs and OAFLSs (P>0.05); Immunofluorescence showed that AQP1 protein was significantly distributed on cell membrane. AQP1 protein expression was very apparent without acetazolamide treatment, whereas the expression was significantly attenuated by acetazolamide in a time-dependent manner., Conclusion: Up-regulation of AQP1 expression in RA synovial membrane may be the one of mechanisms of arthroedema. Acetazolamide can reduce the expression of AQP1 rather than AQP3 in RAFLSs.