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Ciliates are an important component of the rhizosphere microorganism community, but their nutritional contribution to plants has not been fully revealed. In this paper, we investigated the rhizosphere ciliate community of potatoes during six growth stages, illustrated the spatial–temporal dynamics of composition and diversity, and analyzed the correlation between soil physicochemical properties. The contributions of ciliates to the carbon- and nitrogen-derived nutrition of potatoes were calculated. Fifteen species of ciliates were identified, with higher diversity in the top soil, which increased as the potatoes grew, while they were more abundant in the deep soil, and the number decreased as the potatoes grew. The highest number of species of ciliates appeared in July (seedling stage). Among the five core species of ciliates, Colpoda sp. was the dominant species in all six growth stages. Multiple physicochemical properties affected the rhizosphere ciliate community, with ammonium nitrogen (NH4+-N) and the soil water content (SWC) greatly influencing ciliate abundance. The key correlation factors of ciliates diversity were NH4+-N, available phosphorus (AP), and soil organic matter (SOM). The annual average contribution rates of carbon and nitrogen by rhizosphere ciliates to potatoes were 30.57% and 23.31%, respectively, with the highest C/N contribution rates reaching 94.36% and 72.29% in the seedling stage. This study established a method for estimating the contributions of carbon and nitrogen by ciliates to crops and found that ciliates could be potential organic fertilizer organisms. These results might be used to improve water and nitrogen management in potato cultivation and promote ecological agriculture.

With the prevalence of the Internet in society, social media has considerably altered the ways in which consumers conduct their daily lives and has gradually become an important channel for online communication and sharing activities. At the same time, whoever can rapidly and accurately disseminate online data among different companies affects their sales and competitiveness; therefore, it is urgent to obtain consumer public opinions online via an online platform. However, problems, such as sparse features and semantic losses in short-text online reviews, exist in the industry; therefore, this article uses several deep learning techniques and related neural network models to analyze Weibo online-review short texts to perform a sentiment analysis. The results show that, compared with the vector representation generated by Word2Vec’s CBOW model, BERT’s word vectors can obtain better sentiment analysis results. Compared with CNN, BiLSTM, and BiGRU models, the improved BiGRU-Att model can effectively improve the accuracy of the sentiment analysis. Therefore, deep learning neural network systems can improve the quality of the sentiment analysis of short-text online reviews, overcome the problems of the presence of too many unfamiliar words and low feature density in short texts, and provide an efficient and convenient computational method for improving the ability to perform sentiment analysis of short-text online reviews. Enterprises can use online data to analyze and immediately grasp the intentions of existing or potential consumers towards the company or product through deep learning methods and develop new services or sales plans that are more closely related to consumers to increase competitiveness. When consumers experience the use of new services or products again, they may provide feedback online. In this situation, companies can use deep learning sentiment analysis models to perform additional analyses, forming a dynamic cycle to ensure the sustainable operation of their enterprises.

High-temperature molten steel slag is a large amount of industrial solid waste containing available heat energy and resources. This paper introduces an efficient and comprehensive utilization process of high-temperature molten steel slag. The waste heat energy in the high-temperature molten steel slag can be fully recovered through the three-stage heat exchange. Through mass balance and energy balance, the theoretical heat recovery rate can reach 81.42 pct when the waste heat stored in steel slag is converted into usable heat energy, and the exergy efficiency of the overall system is 27.93 pct. When the waste heat stored in the steel slag is converted for electric energy, the theoretical heat recovery rate can reach 24.49 pct, and the exergy efficiency of the overall system is 33.83 pct. When the waste heat stored in steel slag is used for cogeneration, the theoretical heat recovery rate can reach 83.98 pct, and the exergy efficiency of the overall system is 38 pct. The normal-temperature solid steel slag produced by the process is easy for iron selection and subsequent high value-added utilization. The solidification of steel slag in this process consumes a large amount of CO2 so that the free calcium oxide (f-CaO) in the steel slag is fixed, which is more conducive to subsequent utilization, thereby achieving the purpose of energy saving and emission reduction. Compared with the utilization of traditional steel slag, this process can better utilize the energy and resources contained in steel slag and provides a new method for fully utilizing the waste heat energy and resource attributes of high-temperature molten steel slag. Supplementary Information The online version of this article (10.1007/s11663-021-02213-7).

Refractory waste is a typical industrial solid waste. Owing to technical reasons, most of the refractory waste is not efficiently utilized and causes environmental pollution. In this study, we explored a novel technology for the preparation of MgAlON based composite refractories using waste MgO-C and Al2O3-MgO-C refractory materials. The experimental results showed that higher sintering temperatures, enhanced the mechanics of the synthesized MgAlON based composite refractories. Its flexural strength and compressive strength reached 7.7 MPa and 15.87 MPa, respectively, as the sintering temperature increased to 1823 K. Additionally, the slag erosion resistance of the MgAlON based composite refractories was studied and was found to be significantly influenced by the temperature and duration of erosion. The erosion of MgAlON based composite refractories by metallurgical slag was controlled by a combination of chemical reaction and diffusion. The apparent activation energy of slag erosion was approximately 274.6 kJ/mol. During the erosion of MgAlON based composite refractories, the metallurgical slag mainly penetrated the material through its pores. The Si, Ca, and Ti elements in the slag diffused into MgAlON based composite refractories, whereas Mg and Al, diffused into the slag from the MgAlON based composite refractories.

Aiming at the aircraft composite skin grinding, a new three degree-of-freedom (DOF) parallel mechanism with asymmetrical structure (TAM) is proposed to replace manual grinding. The TAM is achieved by integrating one of active limbs into the passive limb while keeping the required DOF unchanged, which is divided into two closed-loop chains: telescopic rod and parallelogram. The inverse kinematics models of the two chains are established according to closed-loop vector method. Thus, the actuation and the constraint Jacobian matrix are obtained. Based on the perturbation principle, the error modeling of the TAM is built. Adopting the constraint Jacobian matrix, 15 uncompensated errors are distinguished from the error model. In order to improve the working accuracy of the TAM, accuracy analysis and synthesis are necessary for all the uncompensated errors. The mapping function reflects the influence of uncompensated errors on the pose accuracy. The global sensitivity evaluation indexes are established by mapping function. Since Sobol sequences are superior in uniformity and convergence, the Quasi-Monte Carlo method based on Sobol sequences (Sobol-QMC) is introduced for sensitivity analysis. Taking the minimum manufacturing and installation costs as the optimization target, the objective function of accuracy synthesis is constructed. Ultimately, the reasonable tolerance zone of each uncompensated error is calculated by genetic algorithm. Simulation is performed by Sobol-QMC to verify the rationality of the optimization. The results show the probability is above 97% where most pose errors are in [[Formula: see text], [Formula: see text]] within the workspace. Therefore, accuracy synthesis is correct and practical.

With the development of medical imaging technology and the introduction of computed tomography (CT), early screening for lung cancer is becoming more and more possible. In this paper, we introduce the method of wavelet dynamic analysis to extract and repair the lung parenchyma, so as to exclude the noise interference outside the lung parenchyma. The algorithm can help us to locate the lung nodules with higher accuracy. Then, the convolution neural network (CNN) optimized by genetic algorithm and the traditional CNN are used to extract the features of CT image of pulmonary nodules. The corresponding features of different images are automatically distinguished. By comparing the accuracy of the two algorithms, it is proved that the CNN optimized by genetic algorithm has higher accuracy. Finally, the CNN optimized by genetic algorithm is used to detect and classify the existing pulmonary nodule images, which provides guidance for CT image detection technology of pulmonary nodule.

In 2012, China's mobile phone users surpassed desktop computers to become the largest Internet terminal, thus irreversibly entering the mobile Internet era. The marketing work of enterprises also appeared a new inflexion point, from the marketing of the industrial economy and information economy to the marketing of the mobile Internet era. In 2021, the total number of mobile Internet users in China exceeded 1.6 billion, and mobile social platform users reached 1 billion. With this, the price of user growth was significantly low, the bonus of traffic growth gradually disappeared, and the stock era has come. It means that enterprises need to change their business ideas and marketing strategies. Operating stock users primarily rely on community interaction and the establishment and maintenance of community emotion in the mobile Internet environment. The success of community operation is the critical factor as the opinion leader of organizers and influencers. The group of mobile Internet opinion leaders is gradually increasing, and professional opinion leaders also appear. This paper studies the impact on consumers' purchase intention from the perspective of information presentation of opinion leaders' commodity recommendation in the mobile network community, enriches the knowledge system of the relationship between opinion leaders and consumers' purchase intention in the mobile Internet environment and has practical significance for the marketing of current enterprises and individuals engaged in business activities.

The ground deicing heating system is an important equipment to ensure flight safety of civil aircraft in winter. As the main element, the heating tube directly affects the working efficiency of the system. The deicing fluid is high viscosity mixture. To improve heating efficiency of deicing fluid, a new special-shaped tube is proposed, which is named double-spiral trapezoidal grooved tube. The upper base width (m), groove depth (h) and base angle (θ) are the important structural parameters of the new tube. The optimal Latin hypercube design is applied to carry out the experiment design of m, h and θ. Nusselt number (Nu), flow resistance coefficient (f) and performance evaluation criteria (PEC) are selected as the optimization objectives. Then, the response surface approximation model is established to conduct sensitivity analysis. Based on the model, NCGA and NSGA-II algorithms are, respectively, introduced to perform the multi-objective optimization. The results show that NSGA-II is better than NCGA. When $$m \in \left[ {0.17, \, 0.33} \right]$$ , $$h \in [1.06, \, 1.08]$$ and $$\theta \in \left[ {84.06, \, 84.75} \right]$$ , the best range of optimization objectives is $$Nu \in \left[ {86.04, \, 87.81} \right]$$ , $$f \in \left[ {0.70, \, 0.73} \right]$$ and $${\text{PEC}} \in \left[ {1.60, \, 1.62} \right]$$ . With the growth of turbulence intensity, PEC > 1, and Nu increases by 4–27%. As a result, the heating efficiency of the new tube is superior to the original tube.

In civil aviation ground deicing system, the traditional reciprocating pump is often used as the power supply device to ensure the physical and chemical properties of high viscosity deicing fluid. The traditional reciprocating pump exist the problem of flow fluctuation. A new horizontal space multiphase crankshaft pump is proposed to suppress the flow fluctuation. The new type of pump adopts segmented crankshaft: each crank pin on the crankshaft drives two connecting rods simultaneously. The connecting rod drives the pistons distributed on both sides of the crankshaft to achieve linear reciprocating motion. Three sections of the crank pin are arranged by 120° phase space circular, and this kind of crankshaft implements multiple phase coupling of piston movement. The hydraulic cylinder adopts the horizontal layout, so the machine structure presents spatial symmetry. A mathematical model of two connecting rods driven by crankpin is established for the new type of pump. The kinematics equation of the piston is solved by the analytical method and then the flow rate of the pump is calculated. In contrast with the experimental data, the new pump can effectively reduce the flow fluctuation.

Based on the classification results of marine structure accidents induced by sea ice, the risk assessment index system of sea ice disasters was established. The possibility coefficient of risks was proposed based on risk factors of sea ice disasters, including sea ice conditions, ice risk status, ice resistance in the design phase, the current defense ability in the operation phase, and management behaviors in the freezing period. The severity index should be determined according to the affected scope, the distribution of affected personnel, and the monitoring ability in emergency. According to the case study and expert evaluation method, the scores and levels of sea ice disaster risk assessment indices were determined. Finally, the sea ice disaster risks of two offshore oil platforms and a coastal nuclear power plant were assessed.

In order to ensure flight safety in cold winter, aircraft ground deicing is crucial and necessary. In Chinese deicing fluid heating system, the helically coiled tube is paramount exchanger to heat deicing fluid. The deicing fluid is ethylene-glycol-based mixture with high viscosity. Aiming at heat transfer enhancement of deicing fluid, ring rib is formed by an embossed tube wall toward the internal of the tube; thus, transversely corrugated helically coiled tube (TCHC) is achieved. Depth and width are two key geometrical parameters of ring rib. Based on field synergy principle, the influence of depth–diameter ratio (H/D) and width-diameter ratio (w/D) is investigated through numerical simulation. The results show that outlet temperature, mean convection heat transfer coefficient, and Nusselt number have similar trends, which first increase and then decrease nonlinearly. The variation of flow resistance coefficient is inversely proportional to Reynolds number. Especially, the effect of H/D is more significant than that of w/D. Field synergy angle and velocity field are also analyzed to reveal the mechanism of heat transfer. TCHC performs better than the original tube. Orthogonal experiment calculates the outlet temperature of TCHC when H/D and w/D change. The combination of H/D=0.075 and w/D=0.5 is best solution. TCHC effectively enhances heat transfer of deicing fluid. Therefore, TCHC is beneficial to improve the deicing efficiency and ensure the flight punctuality.

Manganese and iron oxides catalysts supported on silicalite-1 and titanium silicalite-1 (TS-1) are synthesized by the wet impregnation method for the selective catalytic reduction (SCR) of NOx with NH3 (NH3-SCR), respectively. The optimized catalyst demonstrates an increased NOx conversion efficiency of 20% below 150 &deg, C, with a space velocity of 18,000 h&minus, 1, which can be attributed to the incorporation of Ti species. The presence of Ti species enhances surface acidity and redox ability of the catalyst without changing the structure of supporter. Moreover, further researches based on in situ NH3 adsorption reveal that Lewis acid sites linked to Mn4+ on the surface have a huge influence on the improvement of denitration efficiency of the catalyst at low temperatures.

This study explored the prevalence of irritable bowel syndrome (IBS) and investigated the relation-ship between IBS and disturbed sleep in school-age children in Shanghai, China. Primary, middle and high school students (n = 1542) were recruited from schools in Shanghai. Students completed two questionnaires: the questionnaire for IBS in children and adolescents and the Pittsburgh Sleep Quality Index (PSQI). The overall prevalence of IBS adjusted for cluster effects among students was 18.81%, and prevalence increased with age. Relative to non-IBS students, more IBS students tended to have poor sleep, including quality and duration. IBS is common among children and adolescents in Shanghai, China, and its prevalence increases with age. A tendency toward poor sleep also increases with age. The causal relationship between sleep and IBS needs to be further studied.

The research development and the latest results of far-infrared laser in the last few years were introduced from the following aspects: far-infrared laser, study of basic science, study of astrophysics, communication and military applications, engineering applications, study of medical biology and other applications.

Based on the theory of molecular vibration relaxation, the model of buffer gas effect was built up. By theoretically deducing the vibrational lower-level deactivation rate of operating gas molecule with quantum mechanics, the selection rules of high-efficient buffer gas under different working conditions were educed and tested by experiments. The results could be helpful to the study of large-power wide-range efficient tunable miniature pulsed optically pumped submillimeter wave laser and its application.

Based on the theory of semi-classical density matrix, spike phenomenon of multi-longitudinal-mode CO2-9R(30) optically pumped miniature NH3 molecules far-infrared cavity laser was theoretically studied and the reason of forming spike phenomenon was approved as two aspects: one was the competitive effect caused by the process of AC Stack splitting two photons, which made that the output optical spectral intensity of one AC Stark splitting peak was stronger than that of the other AC Stark splitting peak; the other was the longitudinal-mode spectral characteristics of laser resonant cavity.

Based on the basic theory of molecular vibration relaxation and semi-classical density matrix theory, operating parameters optimization of buffer gas in the process of miniature pulsed optically pumped submillimeter wave laser was systemically studied and the theoretical calculated result was tested by experiments. The result would do favor to develop and study high-power and wide-range tunable miniature and high-efficient pulsed optically pumped submillimeter wave laser and also had some instruction to its application.

Inflammation and reactive oxygen species are associated with the promotion of various cancers. The use of non-steroidal anti-inflammatory drugs (NSAIDs) in cancer prevention treatments has been promising in numerous cancers. We report the evaluation of NSAIDs chemically modified by the addition of a redox-active nitroxide group. TEMPO-aspirin (TEMPO-ASA) and TEMPO-indomethacin (TEMPO-IND) were synthesized and evaluated in the lung cancer cell line A549.We evaluated physico-chemical properties of TEMPO-ASA and TEMPO-IND by electron paramagnetic resonance and cyclic voltammetry. Superoxide dismutase-like properties was assayed by measuring cytochrome c reduction and anti-inflammatory effects were assayed by measuring production of prostaglandin E(2) (PGE(2) ) and leukotriene B(4) (LTB(4) ). MTT proliferation assay and clonogenic assay were evaluated in the A549 lung carcinoma cell line. Maximum tolerated doses (MTD) and acute ulcerogenic index were also evaluated in in vivo.MTD were: TEMPO (140 mg·kg(-1) ), ASA (100 mg·kg(-1) ), indomethacin (5 mg·kg(-1) ), TEMPO-ASA (100 mg·kg(-1) ) and TEMPO-IND (40 mg·kg(-1) ). While TEMPO-ASA was as well tolerated as ASA, TEMPO-IND showed an eightfold improvement over indomethacin. TEMPO-IND showed markedly less gastric toxicity than the parent NSAID. Both TEMPO-ASA and TEMPO-IND inhibited production of PGE(2) and LTB(4) in A549 cells with maximum effects at 100 µg·mL(-1) or 10 µg·mL(-1) respectively.The nitroxide-NSAIDs retained superoxide scavenging capacity of the parent nitroxide and anti-inflammatory effects, inhibiting cyclooxygenase and 5-lipoxygenase enzymes. These redox-modified NSAIDs might be potential drug candidates, as they exhibit the pharmacological properties of the parent NSAID with antioxidant activity decreasing NSAID-associated toxicity.

Er-doped ZnO thin films have been prepared by using inductively coupled plasma enhanced physical vapor deposition at different O2:Ar gas flow ratio (R = 0:30, 1:30, 1:15, 1:10 and 1:6). The influence of oxygen partial pressure on the structural, optical and magnetic properties was studied. It is found that an appropriate oxygen partial pressure (R=1:10) can produce the best crystalline quality with a maximum grain size. The internal strain, estimated by fitting the X-ray diffraction peaks, varied with oxygen partial pressure during growth. PL measurements show that plenty of defects, especially zinc vacancy, exist in Er-doped ZnO films. All the samples show room-temperature ferromagnetism. Importantly, the saturation magnetization exhibits similar dependency on oxygen partial pressure with the internal strain, which indicates that internal strain has an important effect on the magnetic properties of Er-doped ZnO thin films.

Room-temperature ferromagnetism is observed in proton irradiated 4H-SiC single crystal. An initial increase in proton dose leads to pronounced ferromagnetism, accompanying with obvious increase in vacancy concentration. Further increase in irradiation dose lowers the saturation magnetization with the decrease in total vacancy defects due to the defects recombination. It is found that divacancies are the mainly defects in proton irradiated 4H-SiC and responsible for the observed ferromagnetism.

It was found that multi-Raman process and AC Stark effect were essential after study on the effect on wide-band characteristic under different operating gas pressure. Further more the rule of extending the output spectral range was deduced.

Explore the essence of new industrialization, the obstacles and development path in China. It faces the conflict between the resource, environment and the fast developing economy, and the tensions between huge population and employment, and the divergence between the development in urban and rural areas and also the problem of low quality of manufacturing industry, the restrictions imposed by foreign countries and the fierce international competition. Master of Business Administration