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A photocatalyst-free and EDA complex-enabled radical cascade cyclization reaction of inactive alkenes with bromodifluoroacetamides was reported for the divergent synthesis of fluorine-containing tetralones and quinazolinones. In this transformation, persulfates as electron donors and difluoro bromamide as electron acceptors generate the EDA complex. This is a promising photochemical method with advantages such as mild reaction conditions, simple operation, being metal-free, and excellent functional group tolerance.

Surfactant-free microemulsions (SFMEs) exhibited remarkable advantages and potential, attributed to their similarity to traditional surfactant-based microemulsions and the absence of surfactants. Herein, a novel SFME was developed utilizing cosmetically approved materials, such as short-chain alcohol as an amphi-solvent, triethyl citrate (TEC) as the nonpolar phase, and water as the polar phase. 1,2-Pentanediol (PtDO)/TEC/water combination can form the largest monophasic zone, accounting for ∼74% of the total phase diagram area, due to an optimal hydrophilic (water)–lipophilic (TEC) balance. Comparable to surfactant-based microemulsion, PtDO/TEC/water SFME can also be categorized into three types: water-in-oil, discontinuous, and oil-in-water. As TEC or water is increased, or PtDO is decreased, the nanoaggregates in PtDO/TEC/water SFME grow from <5 nm to tens of nanometers. The addition of α-arbutin (ABN) does not disrupt PtDO/TEC/water SFME, but rather enhances its formation, resulting in a larger monophasic area and consistent size (2.8–3.8 nm) through participating in interface assembly. Furthermore, ABN-loaded PtDO/TEC/water SFME exhibits remarkable resistance to dilution, exceptional stability, and minimal irritation. Notably, PtDO/TEC/water SFME significantly boosts ABN’s solubility in water by 2 times, its percutaneous penetration rate by 3–4 times, and enables a slow-release DPPH•radical scavenging effect. This SFME serves as a safe and cosmetically suitable nanoplatform for the delivery of bioactive substances.

Antiangiogenic therapy is an effective way to disrupt nutrient supply and starve tumors, but it is restricted by poor efficacy and negative feedback-induced tumor relapse. In this study, a neuropilin-1 (NRP-1)-targeted nanomedicine (designated as FPPT@Axi) is reported for spatiotemporal tumor suppression by combining photodynamic therapy (PDT) with antiangiogenesis. In brief, FPPT@Axi is prepared by utilizing an NRP-1-targeting chimeric peptide (Fmoc-K(PpIX)-PEG8-TKPRR) to encapsulate the antiangiogenic drug Axitinib (Axi). Importantly, the NRP-1-mediated targeting property enables FPPT@Axi to selectively concentrate at vascular endothelial and breast cancer cells, facilitating the production of reactive oxygen species (ROS) in situfor specific vascular disruption and enhanced cell apoptosis under light stimulation. Moreover, the codelivered Axi can further inhibit vascular endothelial growth factor receptor (VEGFR) to impair the negative feedback of PDT-induced tumor neovascularization. Consequently, FPPT@Axi spatiotemporally restrains the tumor growth through blocking angiogenesis, destroying tumor vessels, and inducing tumor apoptosis. Such an NRP-1-mediated targeting codelivery system sheds light on constructing an appealing candidate with translational potential by using clinically approved PDT and chemotherapy.

ABSTRACTBackgroundAnti-IL-5 monoclonal antibodies (mAbs) targeting IL-5 or IL-5 R α (including mepolizumab, benralizumab, and reslizumab) are widely used for inflammatory diseases such as asthma, eosinophilia, and polyangiitis. However, real-world data regarding its safety in a large sample population are incomplete. So, we evaluated the safety of anti-IL-5 mAbs by pharmacovigilance analyzes based on related adverse events (AEs) from the FDA Adverse Event Reporting System (FAERS).MethodsIn disproportionality analysis, four algorithms were employed to detect the signals of anti-IL-5 mAbs from the FAERS between 2016 and 2022. In addition, we also used MYSQL 8.0, Navicat Premium 15, and Microsoft EXCEL 2019 to analyze the signals of anti-IL-5 mAbs systematically.ResultsThere are 9,476,351 reports collected from the FAERS database, of which 22,174 reports listed anti-IL-5 mAbs as the ‘primary suspected (PS)’ drug. A total of 59 (20 new signals, mepolizumab) and 62 (19 new signals, benralizumab) significant disproportionality preferred terms (PTs) conforming to the four algorithms were retained synchronously. Finally, we detected that the anti-IL-5 mAbs-induced AEs occurred in 31 organ systems (mepolizumab) and 30 organ systems (benralizumab). For mepolizumab and reslizumab, unexpected and new significant PTs of AEs were found, such as asthmatic crisis, chronic obstructive pulmonary disease (COPD), pneumonia, COVID-19, pneumothorax, adrenal insufficiency and so on. Notably, the risk signal of asthmatic crisis for mepolizumab was stronger than benralizumab (ROR 108.04 [95%CI, 96.09–121.47] vs 26.83 [95%CI, 18.91–38.06]). Comparing with mepolizumab and benralizumab, we found the proportion of serious adverse events in mepolizumab was both greater than benralizumab in each age group (≤20, 20–65, and ≥ 65). The median onset time of mepolizumab was 280 days (interquartile range [IQR] 1–367 days).ConclusionAnalysis of FAERS data identified anti-IL-5 mAbs-associated AEs, and our findings supported continuous clinical monitoring, pharmacovigilance, and further studies of anti-IL-5 mAbs. In addition, clinicians may be more aware of the limitations of use in package inserts of anti-IL-5 mAbs: Not for relief of acute bronchospasm or status asthmaticus. Because of some limitations in the FAERS such as self-reports from patients and other confounding factors, the safety of anti-IL-5 mAbs needed more studies in different dimensions, especially the risk of cancer.

The Charpy impact toughness is a crucial mechanical parameter in the application of materials within the realm of engineering. This study represents the pioneering investigation into the influence of different building directions on the Charpy impact toughness of NiTi shape memory alloys (SMAs) produced via laser powder bed fusion (LPBF). Texture analysis reveals that C0 and C90 exhibit a pronounced <001>// building direction (BA), while C45 demonstrates a strong texture along <110> and <111>. The impact test results demonstrate that C0 exhibits superior impact toughness with an absorbed energy of 12.87 J. The fractured surfaces are examined using the scanning electron microscope (SEM) and transmission electron microscope (TEM). Among them, the electron backscatter diffraction (EBSD) results indicate that the samples with higher geometrically necessary dislocation (GND) and kernel average misorientation (KAM) values can effectively reflect superior impact toughness. In contrast, fewer high-angle grain boundaries (HAGBs) are preferable. Due to the adiabatic effect, the phase transformation of the samples from austenite to martensite doesn't appear under the impact loading. Additionally, this paper discusses the impact of texture orientation, defects, and the relationship between loading direction and deposited layers on the impact toughness of the samples. These findings on impact properties would provide valuable guidance for engineering applications of NiTi SMAs.

The Banquan Basin is a pull-apart basin with the largest scale and the most prominent structure due to dextral slip of the Tanlu Fault Zone (TLFZ) in late Cenozoic. The depositional history of the basin records the start time and evolution of the right-lateral strike-slip movement of the TLFZ. This paper studies the sedimentary and tectonic evolution of the Banquan Basin by seismic reflection exploration, borehole detection and cosmogenic nuclide chronology. We analyze the coupling relationship between the pull-apart basin and the strike-slip fault and discuss the start time and tectonic significance of the right-lateral strike-slip of the TLFZ. Our study indicates that the Banquan Basin has undergone three evolutionary stages: weak rifting during the pre-pull-apart period, strong extension during the syn-pull-apart period and subsidence during the post-pull-apart period. This implies that the TLFZ, which controls the evolution of the basin, experienced an evolutionary process of weak activity, intensified activity and migration of activity toward the central basin. The sedimentary filling of the basin has strong response to the episodic pull-apart and extension of the basin. Lying upon the basement of the basin, a thin layer of Miocene mudstone slowly accumulated due to local rifting before the strong pull-apart event. Along with the dextral slipping and pull-apart process, the basin was filled with alluvial fan facies, fluvial facies and floodplain facies strata from bottom to top. The latest tectonic movement of the TLFZ in the North China Block in late Cenozoic was dominated by episodic dextral strike-slip motion, and this deformation pattern started at 4.01±1.27 Ma. The latest tectonic deformation in North China since late Cenozoic was governed by eastward extrusion and tectonic orogenesis of the eastern margin of the Qinghai-Xizang Plateau since late Miocene. The eastward thrusting of the Liupanshan fault zone and sinistral shearing of the Qinling fault zone led to the anticlockwise rotation and pushing of secondary blocks in North China, resulting in a planar bookshelf faulting and rotation pattern. This unique deformation pattern transferred eastwards to the North China Plain at ∼ Ma and the process continues to the present time. This planar bookshelf rotation, accompanied with regional sinistral strike-slip movement of the ∼EW-trending boundary fault zones to the north and south of the North China Block and dextral strike-slip motion of the NNE-trending boundary faults between secondary blocks, is likely to be the long-range effect of the strong extrusion of the eastern margin of the Qinghai-Xizang Plateau.

In recent years, unmanned aerial vehicle (UAV) autonomous flight technology has been applied in many fields. However, in the process of autonomous operation, the UAV may deviate from the set flight path due to various disturbance factors, which results in mission failure. In order to find the abnormal situation in time and take corresponding measures, it is necessary to monitor the operation state of the UAV. Predicting the UAV flight path is the main monitoring method at present; however, the accuracy and real-time of the existing prediction methods are limited. Therefore, this paper proposes an error compensation Bessel bidirectional long short-term memory real-time path prediction model deployed in ground stations. First, because of inconsistency of the units in all directions of the original positioning information provided by global positioning system, the Bessel geodetic coordinate transformation is introduced to unify the units of three-dimensional coordinate data, so as to improve the prediction accuracy. Second, considering the problems of poor data quality and data missing in the operation process, the least square fitting method is used to supplement and correct the positioning coordinate data to obtain more reliable and accurate path observation values as the model input. Finally, a deep learning path prediction model based on bi-directional long short-term memory (BiLSTM) network is constructed, and the appropriate network parameters are determined with the prediction accuracy and time as evaluation indicators. In order to further improve the prediction accuracy, a compensator based on proportional integral differential error control theory is designed according to the output characteristics of the BiLSTM network, which is used for providing compensation values for the prediction results of the model. The training and testing results using the actual flight data of UAV operation show that, under the experimental environment built, the model proposed in this paper can complete the UAV flight path prediction with root mean square error < 1 meter within 0.1 second, and has better performance and higher prediction accuracy than other neural network models.Graphical Abstract

A unified strategy toward asymmetric divergent syntheses of nine C8-ethano-bridged diterpenoids A1–A9(candol A, powerol, sicanadiol, epi-candol A, atisirene, ent-atisan-16α-ol, 4-decarboxy-4-methyl-GA12, trachinol, and ent-beyerane) has been developed based on late-stage transformations of common synthons having ent-kaurane and ent-trachylobane cores. The expeditious assembly of crucial advanced ent-kaurane- and ent-trachylobane-type building blocks is strategically explored through a regioselective and diastereoselective Fe-mediated hydrogen atom transfer (HAT) 6-exo-trig cyclization of the alkene/enone and 3-exo-trig cyclization of the alkene/ketone, showing the multi-reactivity of densely functionalized polycyclic substrates with πC═Cand πC═Osystems in HAT-initiated reactions. Following the rapid construction of five major structural skeletons (ent-kaurane-, ent-atisane-, ent-beyerane-, ent-trachylobane-, and ent-gibberellane-type), nine C8-ethano-bridged diterpenoids A1–A9could be accessed in the longest linear 8 to 11 steps starting from readily available chiral γ-cyclogeraniol 1and known chiral γ-substituted cyclohexenone 2, in which enantioselective total syntheses of candol A (A1, 8 steps), powerol (A2, 9 steps), sicanadiol (A3, 10 steps), epi-candol A (A4, 8 steps), ent-atisan-16α-ol (A6, 11 steps), and trachinol (A8, 10 steps) are achieved for the first time.

The quenching and partitioning (Q&P) process has been adopted innovatively to improve the toughness and wear resistance of Fe-0.44C-1.54B-3.97Mn-0.79Al-0.95Si alloy, and the microstructure, distribution of alloying elements, mechanical properties and dry sliding wear behavior of this alloy in as-cast and heat-treated by Q&P process were systematically investigated. The results show that test alloy consists mainly of martensite, retained austenite (RA) and eutectic boride phases. After being treated by Q&P process, the distribution of alloying elements in the microstructure becomes uniform and the impact toughness increases from 4.02 J cm-2to 6.82 J cm-2, while the mass loss of the alloy is also decreased from 0.064 g to 0.051 g in dry sliding wear test. The improvement of the mechanical properties is attributed to the changes in the during Q&P process, especially the increase in the volume fraction of thin-film RA, as well as the fracture and spheroidization of part of the net-like boride.

A new tandem annulation of p-quinone methides (p-QMs) with ynamides is described. This cascade reaction features a unique combination of (2 + 2) annulation, retro-4π electrocyclization, and imino-Nazarov cyclization, wherein vinyl p-quinone methides (p-VQMs) as one of the key intermediates have been identified chemically. Significantly, an unusual structural reconstruction of p-QMs involving the cleavage of the C5–C6 bond and the late-stage formation of the C4–C6 bond is involved, leading to a methodology development for the construction of functionalized aminoindenes.

This paper presents the method created by the National University of Defense Technology (NUDT) team in the 10th China Trajectory Optimization Competition, which entails a 3-year observation mission of 180 regions on Jupiter. The proposed method can be divided into three steps. First, a preliminary analysis and evaluation via an analytical method is undertaken to decide whether the third subtask of the mission, i.e., exploring the Galilean moons, should be ignored. Second, a near-optimal orbit for magnetic field observation is designed by solving an analytical equation. Third, a set of observation windows and their sequence are optimized using a customized genetic algorithm. The final index obtained is 354.505, ranking second out of all teams partaking in the competition.

Searching for energetic photovoltaic absorbers is a favorable solution to the current energy crisis. As a star material for solar cells, MAPbI3(MA = CH3NH3) has a suitable band gap, strong optical absorption, great defect tolerance, and high certified power conversion efficiency (PCE) up to 25.2%. However, the lead toxicity and poor long-term stability limit its application in photovoltaic devices. To break through these bottlenecks, we design two-dimensional (2D) Dion–Jacobson (DJ)-type (n= 3) chalcogenide perovskites A′La2B3S10(A′ = Ba, Sr, Ca; B = Hf, Zr), with optimal band gap, strong optical absorption, high carrier mobility, and excellent optoelectronic properties, based on the powerful first-principles and advanced HSE06 calculations. Especially, we find that, superior to MAPbI3, 2D A′La2B3S10perovskites have the following several outstanding properties. (1) They are Pb-free and environmentally friendly. (2) The structural stability is better than that of MAPbI3. (3) The direct band gap (∼1.33 eV of BaLa2Hf3S10), i.e., the optimal value of the SQ limit, is more suitable than that of MAPbI3(∼1.55 eV) with a 0.22 eV energy-loss spectrum. (4) The carrier mobility (1.8–2.6 × 103cm2V–1s–1) is larger than that of MAPbI3(∼37 cm2V–1s–1). (5) The optical absorption (∼6 × 105cm–1) in the visible range is three times stronger than that of MAPbI3(∼2 × 105cm–1). (6) The estimated PCE (∼30.9% in BaLa2Hf3S10) is higher than that of MAPbI3(∼30%). These amazing characteristics indicate that 2D A′La2B3S10perovskites are promising absorbers for photovoltaics.

Background: Observational studies have linked hyperuricemia with venous thromboembolism (VTE). We aimed to investigate whether there are causal relationships between uric acid levels and VTE and its subtypes, including deep venous thrombosis (DVT) of the lower extremities and pulmonary embolism (PE). Methods: We utilized Mendelian randomization (MR) analysis to estimate the causal association in European individuals. We extracted two sets of polygenic instruments strongly associated (p&lt; 5 × 10−8) with uric acid from the CKDGen consortium and UK biobank, respectively. Genetic associations with the risk of VTE, DVT, and PE were obtained from the FinnGen biobank. We used the inverse-variance weighted method as the preliminary estimate. Additionally, we employed MR-Egger, weighted median, and Mendelian randomization pleiotropy residual sum and outlier method as complementary assessments. Sensitivity analyses were performed to test for pleiotropic bias. Results: The genetically instrumented serum uric acid levels had no causal effects on VTE, DVT, and PE. Two sets of polygenic instruments used for exposure, along with three complementary MR methods, also yielded no significant association. Conclusions: Our MR analysis provided no compelling evidence for a causal relationship of serum uric acid with the risk of VTE. This suggests that uric acid-lowering therapies in patients with hyperuricemia may not be effective in reducing the likelihood of developing VTE.

Triboelectric nanogenerators (TENGs) are subjected to repeated contact and separations during operation, which inevitably cause damage from mechanical forces, leading to interface mismatch and function loss. Although self-healing property has been utilized to prolong the service life of flexible TENGs, triboelectric nanogenerators which can work stably in extreme mechanical environments have not been developed. Herein, we report a flexible single-mode triboelectric nanogenerator named V-PANI-TENG which not only have strong damage-tolerant ability including puncture-resistant ability to resist sabotage and tear-resistant ability to defend further crack propagation, but also show excellent self-healing performance upon damage based on the well-designed tribolayer PMBEug-OH-V-2–4 and electrode material PMBEug-OH-PANI-20%. Moreover, the V-PANI-TENG can also be used as an efficient self-powered sensor to monitor the movement of human body or detect the road surface roughness. Given the extraordinary durability and unprecedented applications resulting from novel material designs, this work provides an effective way to develop triboelectric nanogenerators which can work stably in extreme mechanical environments and broaden the application scenarios of triboelectric nanogenerators.

This study quantifies the characteristics of different satellite sampling errors in the time series of total precipitable water (TPW) derived from Constellation System for Meteorology, Ionosphere, and Climate (COSMIC) radio occultation, Special Sensor Microwave Imager Sounder (SSMIS), and High‐resolution Infrared Radiation Sounder (HIRS) during the overlapping time period of January 2007 to December 2013. Gap‐free data from ERA5 reanalysis of the European Centre for Medium Range Weather Forecasts are used as reference values. All TPW data are first compared with microwave radiometer measurements from Atmospheric Radiation Measurement Program. In general, they are consistent, with all their regression coefficients being greater than 0.77. Discrepancies in global TPW time series can be mainly attributed to the inherent sampling errors of these three different satellite remote sensing systems. COSMIC has small sampling errors in higher latitudes. But it has scarce samples in tropical regions, which leads to a large sampling error of 3.00 mm in the estimation of global TPW. Sampling in SSMIS is more uniform with mean errors less than 0.5 mm. But the sampling is only over the ocean. Sampling errors in HIRS are larger in tropics and north subtropical areas due to clear sky biased sampling. Moreover, it is significantly correlated with the variability of TPW, whereas the sampling error in COSMIC is less influenced by TPW. Sampling errors will be reduced and more consistent global TPW time series will be derived by simply combining the multisensor samplings together. Sampling differences in COSMIC, SSMIS, and HIRS observations largely explain observed differences between associated TPW time seriesSampling in COSMIC, SSMIS, and HIRS has different characteristics; sampling errors in HIRS are significantly correlated with TPW variabilitySampling errors can be reduced by averaging multisensor sampling; more factors should be considered when merging real satellite data

This study retrospectively evaluated the incidences of small supernumerary marker chromosomes (sSMCs) in prenatal diagnoses and detected with gain of pathogenic copy number variation through array comparative genomic hybridization (CGH) in a laboratory in Taiwan.

Aim:To describe the genomic characteristics of seawater-borne hemolytic Shewanella algaeand its resistance genes. Materials & methods:Whole genome sequence of S. algaeSYT3 was determined using llumina MiSeq platform. Multiple-database-based analysis was performed to identify the genetic background of its hemolytic activity and the antibiotic resistance genes. Results:S. algaeSYT3 possesses a homolog of the hlyoperon involved in the synthesis of hemolysin. We also identified candidate genes associated with resistance to β-lactam antibiotics (blaOXA-55) and fluoroquinolone (qnrA3). Conclusion:The study provides an insight into the hemolytic activity of S. algae. Our findings also suggested S. algaeas a potential reservoir of antimicrobial resistance determinants.

Amino acid metabolism is regulated according to nutrient conditions; however, the mechanism is not fully understood. Using the holometabolous insect cotton bollworm (Helicoverpa armigera) as a model, we report that hemolymph metabolites are greatly changed from the feeding larvae to the wandering larvae and to pupae. Arginine, alpha-ketoglutarate (α-KG), and glutamate (Glu) are identified as marker metabolites of feeding larvae, wandering larvae, and pupae, respectively. Arginine level is decreased by 20-hydroxyecdysone (20E) regulation via repression of argininosuccinate synthetase (Ass) expression and upregulation of arginase (Arg) expression during metamorphosis. α-KG is transformed from Glu by glutamate dehydrogenase (GDH) in larval midgut, which is repressed by 20E. The α-KG is then transformed to Glu by GDH-like in pupal fat body, which is upregulated by 20E. Thus, 20E reprogrammed amino acid metabolism during metamorphosis by regulating gene expression in a stage- and tissue-specific manner to support insect metamorphic development.

The total dose effect of 60Co γ-rays on 0.8-μm H-gate partially depleted-silicon-on-insulator NMOS devices was investigated at different irradiation doses. The results show that the shift in saturation current at high dose rate is greater than that at low dose rate, due to increase in interface-state density with decreasing dose rate; the scattering effect of interface state on electrons in the channel causes degradation in carrier mobility; and the body current and transconductance of the back gate enhance low-dose-rate sensitivity when the irradiation is under OFF-bias. A double transconductance peak is observed at 3 kGy(Si) under high dose rates.

Gastric cancer (GC) is a common malignant tumor worldwide. Modified Gui-shao-liu-jun-zi decoction (mGSLJZ) is a clinically effective traditional Chinese medicine (TCM) compound in GC treatment. This study aimed to analyze main chemical substances of mGSLJZ and investigate active ingredients and molecular mechanism of mGSLJZ against GC.

A strategy utilizing silver-catalyzed oxidative decarboxylation radical cascade cyclization of arylthiodifluoroacetic acids with alkenes for the simple and efficient preparation of difluoromethylated thiochromanes and 2,2-disubstituted-N-arylbutanamides derivatives has been developed. This approach includes good functional group tolerance, easily accessible starting materials, and operational simplicity.

The Constellation Observing System for Meteorology, Ionosphere and Climate-2/Formosa Satellite Mission 7 (COSMIC-2) Global Navigation Satellite System (GNSS) Radio Occultation (RO) constellation is the follow-on to the highly successful COSMIC-1 program. The GNSS RO atmospheric soundings have historically been used to generate Community Radiative Transfer Model simulated background (B) microwave (MW) brightness temperature data needed to monitor NOAA operational MW sounding instrument observed (O) antenna temperature (Ta) product quality. This study is motivated by the need to determine the impact of COSMIC-2 RO soundings on this critical long-term monitoring capability. This study is based on individual MW sensor O-B Ta bias (∆Ta) statistics and "double-difference" inter-sensor Ta bias (δTa) statistics for two time periods. Time Period 1 (TP1—May 1, 2017, to September 30, 2019) exclusively uses COSMIC-1 and Korea Multi-Purpose Satellite-5 soundings, while Time Period 2 (TP2—October 1, 2019, to December 31, 2020) expands the analysis with COSMIC-2 soundings. The TP1 and TP2 ∆Tastatistics comparisons indicate COSMIC-2 data population augmentation and latitudinal distribution impact the MW sounder performance monitoring tool transition from TP1 to TP2. COSMIC-2 competently supports long-term MW individual sensor and inter-sensor product monitoring for MW radiometer channels with weighting functions that peak between 8 and 30 km. Individual sensor ∆Tamonitoring for other microwave channels that depend on COSMIC-2 data below 8 km and from 30 km to 60 has limitations, but these limitations are shown not to inhibit critical δTamonitoring.

This work researched the impact of total dose irradiation on the threshold voltage of N-type metal oxide semiconductor field effect transistors (nMOSFETs) in silicon-on-insulator (SOI) technology. Using the subthreshold separation technology, the factor causing the threshold voltage shift was divided into two parts: trapped oxide charges and interface states, the effects of which are presented under irradiation. Furthermore, by analyzing the data, the threshold voltage shows a negative shift at first and then turns to positive shift when irradiation dose is lower. Additionally, the influence of the dose rate effects on threshold voltage is discussed. The research results show that the threshold voltage shift is more significant in low dose rate conditions, even for a low dose of 100 krad(Si). The degeneration value of threshold voltage is 23.4 % and 58.0 % for the front-gate and the back-gate at the low dose rate, respectively.

The effect of calcium sulfates varieties on the properties of calcium aluminate cement-based self-leveling mortar have been investigated, and the hydration kinetics, hydrated products and microstructures are characterized by isothermal calorimeter, X-ray diffraction and mercury intrusion porosimetry, respectively. The results show that the technological properties of mortars are significantly affected by calcium sulfate varieties and content. The setting times are shortened drastically with the addition of calcium sulfates. Mortars with hemihydrate show higher early strength and less drying shrinkage. In contrast, using anhydrite in mortars cause lower strength and higher drying shrinkage at early age but larger growth of strength in the late. The increasing calcium sulfates content may result in the delay of main hydration peak in the heat evolution curve. For formulation with hemihydrate, the appearance of main hydration peaks are advanced compared with formulation without addition of calcium sulfates. Moreover, mortar microstructures are optimized by addition of β-hemihydrate, the proportion of large pores are lower than that of mortars with anhydrite.

The safety and comfort of the ship can be affected by the vibration of pumps, which is introduced by the interaction between structure and fluid during the running of pumps. It is necessary to investigate the vibration of pumps; however, there are few existing papers regarding the effect of process parameters on the vibration characteristics of pumps. Considering bearing process parameters, a dynamic virtual prototype model is presented in this paper. The model takes the bearing clearance and preload force of deep groove ball bearings as key parameters to study the vibration of a type of centrifugal pump. It is concluded that the pump vibration does not decrease continuously with increasing bearing preload. The vibration characteristics of the pump can be effectively improved by reasonable adjustment of these two parameters. The experimental results obtained in the test rig show an agreement with model calculation. By choosing the optimal bearing clearance and preload, the peak at the shaft frequency can be reduced by 7.95 dB.

The work considers the application of a magnetic spectrometer (MS) for analyzing the hydrogenation of metals (particularly, titanium and copper). Therefore, for the sake of increasing the sensitivity of the magnetic spectrometer, the following ratios are introduced: (ΔU/U)/(Δd/d) (where ΔU/U is the relative change of the MS signal and Δd/d is the relative change in the thickness of a sample), (ΔU/U)/(Δδ/δ) (where Δδ/δ is the relative change in the depth of eddy current penetration into metal) and (ΔU/U)/(ΔS/S) (where ΔS/S is the relative change in the area of sample). These parameters allow to eliminate or reduce the error in determining the conductivity value. Parameter β that is equal to the product of the sample area and the inverse value of eddy current penetration depth into metal corresponds to the effectiveness of the current penetration into metal. The authors derived a formula that ties the electric conductivity of metal to the number of implanted hydrogen atoms, which allows determining the composition of titanium hydride at different depth of metal.