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Generally, an optical switch is only suitable for a narrow and particular field. In this paper, a microfluidic matrix optical switch based on the electrowetting-on-dielectric driving technology is proposed, which can be applied in a wide range of optical communication and optoelectronic systems. It has the advantages of simple structure, convenient operation, polarization independence and easy integration of large matrix switches. Here the structure and working principle of this matrix optical switch are given, and the matrix driving circuit is designed. The operating voltage of the optical switch is 58V. The results show that the response time is 120 ms from "on" to "off" and is 100 ms from "off" to "on". The insertion loss is 0.26 dB, which is much lower than that of general matrix optical switches, and the extinction ratio is 139.7 dB. Moreover, two application schemes are given, namely, a photoelectricity display and a multi-beam array switch. Our work can provide a new idea for large-scale integrated matrix switches and promote the application of optofluidics in optoelectronic systems.

High entropy alloy is defined as an alloy containing four or more main elements. The atomic fraction of the main elements is greater than 5% and not more than 35%, which has excellent properties such as high strength, high wear resistance and high corrosion resistance. Refractory high-entropy alloy is a new type of superalloy designed and developed based on high-entropy alloy of refractory elements, which has broad application prospects in aerospace, petrochemical and other fields, and is expected to replace traditional superalloys. This paper reviews the composition design of refractory high-entropy alloys from the aspects of element selection and addition of trace elements, and its phase composition has single-phase structure and duplex structure, and the preparation method and performance characteristics of refractory high-entropy alloys are studied, and finally gives the problems and challenges faced by refractory high entropy alloys. This review provides a valuable reference for researchers in the component design, microstructure regulation and performance development of refractory high entropy alloys.

Background Restless leg syndrome (RLS) is a type of sensorimotor disorder, and clinical workers have made some recent developments in its pathological mechanism and treatment. Epidemiological studies have verified that RLS is notably associated with neuro-psychological diseases, kidney disease, cerebro-cardiovascular diseases, nutritional and metabolic diseases, and pregnancy disorders. The diagnostic rate of RLS is low due to lack of specific clinical symptoms, clear genetic and biological markers, and polysomnography (PSG) diagnostic criteria. There are several sleep centers in foreign countries where the suggested immobilization test (SIT) has been applied in clinical treatment and research about RLS. Objective To evaluate the clinical significance of SIT in RLS diagnosis. Methods The study enrolled 220 patients who visited the PKU-UPenn Sleep Center, Peking University International Hospital with a main complaint of discomfort in bilateral lower limbs during daytime rest or before sleep, and 150 healthy volunteers from January 2016 to June 2021. Discomfort in lower limbs was measured in healthy volunteers and RLS cases at baseline. The actual limb movement index (LMI) , periodic limb movements while awake index (PLMWI) , and periodic limb movement in sleep index (PLMSI) were evaluated with PSG. PLMWI≥40 times/h during SIT and >3 increment of self-assessment score of lower limb discomfort after SIT than the last assessment or one of early assessments were considered as positive SIT. Results Among the 220 RLS patients, 9 patients did not finish the SIT due to severe symptoms-induced unbearable discomfort during resting sit, the other 211 patients (95.9%) together with all healthy volunteers (100.0%) who successfully finished the SIT were finally included. There were significant differences in LMI, PLMWI and PLMSI during the SIT between healthy volunteers and patients (P

The Ke'eryin area in Sichuan province is one of the large rare metal ore concentration areas in the Songpan–Garze metallogenic belt. Numerous granite pegmatite dikes spread around the Ke'eryin mass. However, locating rare metal dikes in such a large pegmatite field has always been one of the challenges in this region. This paper summarized the geochemical element distribution in the Ke'eryin pegmatite and put forward geochemical indexes, e.g., characteristic element indexes, indicator indexes and grade indexes, to locate rare metal ore in the Ke'eryin area based on a systematic petrogeochemical analysis of two-mica granite, pegmatite microcline albite granite, different pegmatite types and typical deposits. Characteristic element indexes include Li, B, Sn, Rb, Be, Nb and Ta, etc. Indicator indexes for lateral variation are Cs, Tl, F, Zr, Y and ΣREE elements as well as values, e.g., TiO2/Ta, Zr/Hf, Ta/Zr, Nb/Ta, K/Na, etc., while indicator indexes for vertical variation include B, U, Zr, Be, Sn, Rb, Sr, Ba, Tl and In, etc. The variation in these indexes can be used to locate rare-metal-mineralized pegmatite, indicating ore bodies in a deep basin. Grade indexes are aluminum saturation index（A/CNK, A/NK）and rittmann index(σ), etc. Li ore grade is positively correlated with aluminum saturation but is negatively correlated with alkalinity. Grade index variation is a good indicator of lithium enrichment in ore bodies.

In this article, we prepared novel basalt fiber (BF)-reinforced polypropylene (PP) composites based on the synergistic reinforcement of cellulose nanocrystals (CNCs). First, we compared the enhancement effect of CNCs and silane coupling agent-modified BFs on PP, showing that the enhancement effect of the former was more significant. Subsequently, to further improve the mechanical properties of the composites, CNCs were introduced into the BF-reinforced PP composite system as the third phase, and the results suggested that their combination with BFs could synergistically strengthen the PP matrix composites. Simultaneously, the study also shows that when the mass percentage of CNCs and BFs are 1 and 30%, respectively, the composite achieves the highest mechanical strength, which is 64.31% higher than that of the PP matrix. The systematic characterization revealed the synergistic enhancement mechanism: on the one hand, CNCs not only promoted the improvement of PP crystallinity by heterogeneous nucleation but also formed a wedge-shaped structure between them and BFs through hydrogen bonding to prevent PP molecular movement; on the other hand, the BFs promote not only the extrusion crystallization of the resin matrix but also the network structure formed by the appropriate content of BFs can realize the rapid transmission of external stress.

ASAP3 is involved in a variety of biological activities, including cancer progression in humans. In adult glioma, we explore the effects of ASAP3 and NOTCH3 and their relationships on prognosis. The Oncomine, TIMER, and Gene Expression Profiling Interactive Analysis databases were used to investigate ASAP3 expression. Immunohistochemistry was used to assess the levels of ASAP3 and NOTCH3 expressions. The effects of ASAP3 and NOTCH3 on prognosis were assessed using survival analysis. The results revealed that the amount of ASAP3 mRNA in gliomas was much higher than in normal tissue (P < 0.01). Glioma patients with high ASAP3 mRNA expression had a worse overall survival and progression-free survival. ASAP3 overexpression is directly associated with the NOTCH signaling system. Immunohistochemistry revealed that ASAP3 and NOTCH3 were overexpressed in glioblastomas (GBMs). ASAP3 expression was associated with age, recurrence, tumor resection, postoperative chemoradiotherapy, World Health Organization (WHO) grade, and Ki-67 expression. ASAP3 expression was related to the isocitrate dehydrogenase-1 mutation in low-grade glioma. Gender, local recurrence, tumor resection, postoperative radio-chemotherapy, WHO grade, recurrence, and ATRX expression were all associated with NOTCH3 expression. ASAP3 was shown to be positively associated with NOTCH3 (r = 0.337, P = 0.000). Therefore, ASAP3 and NOTCH3 as oncogene factors have the potential to be prognostic biomarkers and therapeutic targets in adult glioma.

BACKGROUND Human health risks and potential environmental geological hazards caused by contaminated sites have been paid much attention. Monitored natural attenuation (MNA) is recognized as a preferred remediation technique. However, for sites with non-aqueous phase liquids (NAPLs), the problem of "tailing rebound" caused by the residue of NAPLs in the source area poses a challenge to the MNA technology. In recent years, the emergence of natural source zone depletion (NSZD) enriches the connotation of MNA remediation, and it is a potential way to solve the problem of "Tailing & Rebound". OBJECTIVES To summarize the research process and latest achievements of NSZD for light non-aqueous phase liquid (LNAPL) contaminated sites. METHODS A comprehensive review was conducted on the literature on NSZD for LNAPL contaminated sites from the end of the 1990's. The conceptual models of vertical zoning natural elimination in LNAPL source areas have been reviewed. The key control factors on NSZD and main scientific and technological challenges for future research have been fully discussed. RESULTS The research shows that: (1) since 2000, the research on MNA remediation has gradually shifted from groundwater pollution plume attenuation to natural depletion of vadose zone source areas; (2) The natural elimination process of aeration zones has proved to be the key biological process of NSZD, accounting for 90%-99% of the total mass loss of LNAPLs; (3) biodegradation in the volatilization process of LNAPL is the major research field of NSZD. The following research methods of NSZD are established: (1) the NSZD method can be divided into three parts: LNAPL source area plume identification, qualitative judgment and quantitative estimation; (2) The Concentration Gradient Method, CO2 Fluxes Method (including Dynamic Closed Chambers and CO2 Traps) and Thermal Gradient Method are three major methods for quantitative estimation. CONCLUSIONS Based on the existing research progress and challenges, the key scientific problems to be solved in the application and promotion of NSZD include identifying the composition change of LNAPLs in the source area, clarifying the speed limiting factor for natural elimination in the source area, and developing appropriate monitoring methods for degassing and bubble escape.

Scanned reactive-ion-beam etching method was proposed to transfer two-dimensional mask patterns into quartz substrate, which would produce a larger-size and polarization-independent two-dimensional grating. This method was realized by moving grating substrate in a unidimensional scanning manner and adjusting ion beam density in the vertical scanning direction. Graphite plates between the ion beam source and the substrate were used to correct the beam density. The original Gaussian ion beam density was changed to a uniform distribution to establish a knife-edge shape around the vertical scanning direction. Therefore, a large-area pattern with consistent depth and duty cycle would be engraved into a quartz substrate. A two-dimensional, 1200 groves/mm grating with an 85-mm × 85-mm area was fabricated under scanned reactive-ion-beam etching method and exhibited a 0.197λ (λ = 632.8 nm) diffraction wave front. At 780 nm, the efficiency nonuniformity was less than 9%, and the average diffraction efficiencies of transverse-magnetic and transverse-electric polarized light were 57.2 and 58.0%, respectively. The large-size two-dimensional grating with uniform diffraction efficiency and polarization independence enabled grating displacement measurement with high resolution, long measurement range, multiple degrees of freedom, and potential miniaturization.

Traditional orchard production is facing problems of labor shortage due to the aging, difficulties in the management of agricultural equipment and production materials, and low production efficiency which can be expected to be solved by building a smart orchard that integrates technologies of Internet of Things(IoT), big data, equipment intelligence, et al. In this study, based on the objectives of full mechanization and intelligent management, a smart orchard was built in Pinggu district, an important peaches and pears fruit producing area of Beijing. The orchard covers an aera of more than 30 hm2 in Xiying village, Yukou town. In the orchard, more than 10 kinds of information acquisition sensors for pests, diseases, water, fertilizers and medicines are applied, 28 kinds of agricultural machineries with intelligent technical support are equipped. The key technologies used include: intelligent information acquisition system, integrated water and fertilizer management system and intelligent pest management system. The intelligent operation equipment system includes: unmanned lawn mower, intelligent anti-freeze machine, trenching and fertilizer machine, automatic driving crawler, intelligent profiling variable sprayer, six-rotor branch-to-target drone, multi-functional picking platform and finishing and pruning machine, etc. At the same time, an intelligent management platform has been built in the smart orchard. The comparison results showed that, smart orchard production can reduce labor costs by more than 50%, save pesticide dosage by 30% ~ 40%, fertilizer dosage by 25% ~ 35%, irrigation water consumption by 60% ~ 70%, and comprehensive economic benefits increased by 32.5%. The popularization and application of smart orchards will further promote China's fruit production level and facilitate the development of smart agriculture in China.

Abstract Backgrounds In the face of the new environment, different individuals have different reactions. Those who have good adaptability constantly establish individual self-efficacy through making friends and completing their studies, thus forming a good dependency with the university environment. However, individuals with poor ability to adapt to the new environment will have some bad phenomena, such as truancy, weariness and self denial. As a result, the students’ adaptations of to the growth environment where in universities are the important topics in recent years. Methods Present study introduces irrational beliefs to investigate the effects of parenting mode on maladaptation of university students. The questionnaires based on simplified parenting mode (Chinese), irrational belief and adaptability were administered in a survey of 510 university students in Zhanjiang on October, 2021, the list of students of Guangdong Ocean University is taken as the sampling frame and determined by random sampling. Parenting mode was used as the independent variable, while the emotionally warm, overprotective and rejecting types were used as the indices. Further, the irrational beliefs including summary comments, awful beliefs and low tolerance to setbacks as well as maladaptation were included in the mediation model for analysis. Results The results showed that the rejection parenting mode was negatively related with absolute requirements (r = − 0.143), and learning motivation (r = − 0.157), interpersonal adaptation (r = − 0.283) and physical and psychological adjustment (r = − 0.083). Overprotection was negatively correlated with absolute requirements (r = − 0.042) and interpersonal adaptation (r = − 0.042). The mediating effect of irrational beliefs (low tolerance to setbacks, awful beliefs and absolute requirements), the lower and upper limits of Bootstrap confidence interval were 0.135 and 0.461, respectively, excluding 0, which indicated that the mediating effect is true. Conclusion Through the analysis of the data, this study believes that irrational beliefs such as low tolerance to setbacks, awful beliefs and absolute requirements mediate the effects on school adjustment. Negative parenting modes such as overprotection and rejection inculcate irrational beliefs, resulting in maladaptation of university students.

Injection of piperacillin sodium and tazobactam sodium can be used for systemic and/or local infections, including soft tissue infection, bacterial septicemia, bone and joint infection, multiple bacterial infection （various bacterial infections in suspected infection sites）. As a commonly used anti-inflammatory drug for the treatment of burns and wounds, the most common adverse reactions are skin reactions, gastrointestinal symptoms and anaphylaxis. However, central nervous system symptoms, such as convulsion or numbness, are extremely rare. In this article, clinical data were retrospectively analyzed and literature review was performed. The diagnosis and treatment of one case of systemic muscle tremor and numbness induced by injection of piperacillin sodium and tazobactam sodium were reported, aiming to captivate the attention of clinicians, deepen the understanding of adverse reactions induced by this kind of drugs, reduce the incidence of adverse outcomes.

Large flexible airship is an important platform for“long stay in the air”in near space.It is of important national defense and civil value.It is one of the hotspots in the field of structural engineering of aerostat in recent years.The main airbag is the core structural component of the flexible airship.In order to study the influence of the flow field around the main airbag of the large flexible airship on its modal performance,the air around the main airbag of the flexible airship is assumed as incompressible fluid,adding the influence of air vibrating with the airbag as an additional mass to the capsule structure.The dry and wet modal analysis of the main airbag under 5 different internal pressures is completed by the additional mass calculation method based on the potential flow theory.The first three order of vibration modes and frequencies of the internal pressure of the main airbag at 2、4、6、8 and 10 k Pa is obtained by experiment.The test and analysis results show that:the first 3 order of vibration frequencies of dry and wet mode gradually increase with the increase of internal pressure,under the same internal pressure,the wet modal frequency of the main airbag reduced when considering the influence of the air surrounding the airbag body with the structural vibration.

A liquid chromatography-tandem mass spectrometry (LC-MS) method for screening 53 stimulants in animal foods was developed. The method uses 2% formic acid-acetonitrile/water (80/20) as the extraction solvent and carries out one-step purification by FaVEx-AP solid phase extraction column. Endeavorsil C18 column was used for separation, and multiple reaction monitoring (MRM) mode was used for data acquisition and analysis. The results showed that the correlation coefficient (R2) was more than 0.99. The detection limit and quantification limit were 0.25–10μg/kg and 1–10μg/kg. The recoveries were 62.25%–123.32% and the relative standard deviation (RSD) was 1.17%–22.03%. The method is rapid, simple and accurate, and is suitable for the determination of 53 kinds of stimulants in animal-derived foods.

Lithium slag(LS) is industrial solid waste during the production of lithium carbonate. LS has pozzolanic effect and replace cement to achieve the purpose of protecting the environment and saving resources. In order to clarify the influence of fineness and content of LS on the performance of cement mortar. The effects of different fineness and content of LS powder on the workability, mechanical properties and microscopic properties of cement mortar were studied. The results shown that the grinding time refined the particle size of LS and increased the particle content in the range of 0.95μm~5.68μm. Fineness of LS had little effect on the workability and mechanical properties of cement mortar. Excessive LS had significant negative impact on workability and mechanical properties of cement mortar. When the content of LS was 10 %, the heat release, the production of Ca(OH)2 and ettringite of cement paste increased. Early mechanical property of cement mortar was unreduced and effectively improved later mechanical properties under this content. The research can provide data support for the application of LS in practical engineering.

Taking the SaErTU and Putaohua oil layers in the L29 well area of LHP oilfield in the northern Songliao Basin as the research object, In response to the difficulty of interference between thin interbedded sand and mudstone and strong reflection between strata, which have a significant impact on fine prediction of sand bodies, a stratigraphic model is established based on the geological characteristics of the target layer to eliminate the impact of stratigraphic reflection; Then add a thin layer of sand body to its interior, establish a thin interlayer model, and obtain a geological model that is more in line with the actual situation of the target layer. Using forward simulation, analyze the seismic response characteristics of sand bodies, extract 30 seismic attributes from 4 categories: amplitude statistics, composite seismic trace statistics, sequence and frequency spectrum statistics, and calculate the correlation between cumulative sandstone thickness and seismic attributes, and select a sensitive seismic attribute set;By combining sedimentary and drilling data, the seismic attribute with the highest sensitivity to the target layer is selected. The multi-level dimensionality reduction and gradual improvement of seismic attribute selection methods using “model forward modeling, attribute analysis, relevant optimization, and drilling implementation” can effectively improve the prediction accuracy of thin interbedded sand bodies and greatly reduce the risk of oilfield exploration and development.

Fracturing technology is the main measure to increase production and injection in oilfield production. With the gradual expansion of the scale of polymer flooding, the proportion of fractured Wells also increases year by year. How to maximize the benefits of fracturing measures has become the key technology, and the timing of fracturing is a major factor affecting the fracturing effect. By studying the fracturing time and effect of fracturing Wells in the industrial zone of polymer flooding, the optimal fracturing time of injection-production Wells is given. The fracturing time of injection Wells should be dominated by blank water drive stage and water-cut decline period. The producing Wells with low liquid production strength and low flow pressure are suitable for whole-well fracturing in water-cut decline period, and the thick-injection-thin production Wells dominated by river channels are suitable for fracturing in low-water cut period. Thin and differential Wells with differential production are suitable for fracturing during water-cut recovery period.

The development of food infrared heating theories were discussed in this review, and the advancement of infrared heating in food processing were summarized. Moreover, the principle of food processing and process optimum method in various food infrared thermal treatment technologies, including sterilizing, thawing, blanching, baking, peeling and drying processes were also discussed.

BACKGROUND Porosity is a key parameter for exploration and evaluation of shale gas reservoirs. Rapid and accurate determination of shale porosity is crucial for reserve calculation. At present, there are helium gas method, liquid saturation method and image analysis method applied to shale porosity determination, but the comparison between methods and laboratories is lacking. OBJECTIVES To evaluate the applicability of different methods for determining shale porosity. METHODS The characteristics of 69 shale samples from the Longmaxi Formation were studied by analyzing and testing techniques such as X-ray diffraction, argon ion polishing-scanning electron microscopy, and mercury injection-nitrogen adsorption method. Comparison experiments for porosity measurement were conducted among helium method, liquid saturation method and image analysis method. RESULTS The Longmaxi Formation shale had high clay content, many organic pores, small pore throats, and poor seepage capacity, which made it difficult for foreign liquids and gases to quickly enter the pores, which required high resolution of core image data. The liquid saturation method (alcohol method) used 20MPa pressure to saturate the sample for 24 hours, resulting in core damage, and the measured porosity deviated from the true value. The image analysis method ignored the micropores (pore size < 2nm) and mesopores (pore size < 50nm) in the mineral matrix and other factors, making the porosity measurement result unreliable. The porosity measurement result of the helium method was closely related to the drying temperature and stabilization time. The higher the temperature, the larger the measured porosity, and if the stabilization time is too short, the porosity result will be smaller than the real values. CONCLUSIONS After drying the core at 60℃ for more than 24 hours to a constant weight, by setting a reasonable stabilization time, accurate porosity results can be obtained by the helium method. Properly increasing the injection pressure helps to speed up the experimentation rate.

Objective To evaluate the efficacy and safety of yinqiao qingre tablet in treating common cold with wind-heat type.Methods The randomized, double-blind, placebo, parallel control research were applied to this study. The eligible subjects were divided into a experimental group, a positive control group and a placebo control group. The test drug was yinqiao qingre tablet, positive control drug was yinqiao jiedu tablet, and simulation drugs were yinqiao qingre simulation tablet and yinqiao jiedu simulation tablet. The experimental group was given yinqiao qingre tablet and yinqiao jiedu simulation tablet, the positive control group was given yinqiao qingre simulation tablet and yinqiao jiedu tablet, and the placebo control group was given yinqiao qingre simulation tablet and yinqiao jiedu simulation tablet.The course of treatment for each group was 3 days. Before and after treatment, the disappearance rate of major symptoms, individual symptom scores, efficacy of TCM syndrome, change of temperature, used of antipyretic analgesics and safety were evaluated. Results The disappearance rate of major symptoms was 62.12% in experimental group, was the highest among three groups(P

Thermoplastic vulcanizate based on ethylene-vinyl acetate copolymer/nitrile rubber (EVA/NBR TPV) was prepared by dynamic vulca-nization method, the effect of the mass ratio of rubber to plastic on the superhydrophilic behavior of EVA/NBR TPV surface was researched, the microstructure and super hydrophilicity of EVA/NBR TPV super hydrophilic surface were studied, and the hydrophilic mechanism was preliminarily discussed. The results showed that the surface hydrophilicity of EVA/NBR TPV prepared by template method with water-resistant sandpaper as template was better when the mass ratio of rubber to plastic of EVA/NBR TPV was 20/80. The surface hydrophilicity of EVA/NBR TPV film with the mass ratio of rubber to plastic of 20/80 was the best when the sandpaper NO 1000 was used as the template at 165 °C after being preheated for 10 min, being hot pressed for 3 min and being cold-pressed for 5 min.

Accurate and rapid prediction of reentry trajectory and landing point is the basis to ensure the reentry vehicle recovery and rescue, but it has high requirements for the continuity and stability of real-time monitoring and positioning data and the fidelity of the reentry prediction model. In order to solve the above contradiction, based on the theory of relative entropy and closeness in fuzzy learning, research on real-time evaluation of reentry reachability is presented in this article. With the Monte Carlo analysis data during the design and evaluation of the reentry vehicle control system, the reentry trajectory feature information base is designed. With the matching identification decision strategy between the identified trajectory and trajectory feature base, the reachability of the reentry vehicle, reachable trajectory, and landing point can be predicted. The simulation results show that by reasonably selecting the time window and using the evaluation method designed in this article, making statistics of the trajectory sequence number and frequency identified based on relative entropy and closeness method, the reachability evaluation results can be given stably, which is suitable for the real-time task evaluation of TT&C system.

Although it is widely acknowledged that urban expansion is one of the most important processes affecting global sustainable development, an increasing number of cities are shrinking across the world. There is growing interest in urban shrinkage because it has reached a global scale, decisively affecting the fate of many cities over the past half-century. In recent years, urban shrinkage has become a big challenge for China's new-type urbanization construction and sustainable development due to slower economic growth, rapid aging, and massive migration. Although research on urban shrinkage has rapidly increased in recent years, many theoretical and methodological issues must be further discussed, such as the identification of shrinking cities from multiple dimensions and the dynamic process of urban shrinkage. Therefore, this paper proposes a new, multi-dimensional analysis framework from the following aspects of urban shrinkage: types of shrinking dimensions, number of shrinking dimensions, and temporal evolution. Subsequently, this framework was employed to explore the spatial-temporal evolution characteristics of shrinking cities in China by means of GIS spatial analysis and grey relational analysis. The results indicate the following: 1) this new framework presents satisfactory flexibility and higher adaptability, and it helps to enhance the comparability of shrinking city studies. Furthermore, it has considerable potential in promoting the construction of a multi-dimensional typology for shrinking cities and analyzing the possible temporal evolution paths of urban shrinkage. 2) In the four periods of 1995-2000, 2000-2005, 2005-2010 and 2010-2015, the proportion of population shrinking cities accounted for 9.55%, 20.34%, 15.34% and 19.72% of the total cities in China respectively; while the proportion of economic shrinking cities were 5.32%, 4.85%, 0.47% and 8.29%, and the proportion of space shrinking cities were 7.04%, 3.44%, 3.76% and 1.72% respectively. Population shrinkage is the main characteristic of urban shrinkage in China. From the perspective of spatial distribution, population shrinkage is a national phenomenon because such cities are distributed in various regions in China. As for temporal evolution, the proportion of population-shrinking cities in Western and Northeast China, with relatively lagging economic development, increased significantly. 3) The extent of urban shrinkage in China is not very serious because the population shrinkage rates of the majority of shrinking cities were less than 3%, and only two continuous population-shrinking cities have been identified: Yakeshi (Inner Mongolia) and Qidong (Jiangsu Province). Furthermore, no continuous economic- or space-shrinking city exists in China. 4) Three interesting paradoxes were revealed regarding urban shrinkage in China: the built-up areas in 93.03% population-shrinking cities were expanded, the gross domestic product (GDP) of 92.37% population-shrinking cities were increased, and the built-up areas of 94.57% economic-shrinking cities were expanded. The emergence of the above paradox has a strong relationship with China's factor-dependent economic growth model and local governments' land financing model.

Abstract Background Symptomatic pseudarthrosis and cage migration/protrusion are difficult complications of transforaminal or posterior lumbar interbody fusion (TLIF/PLIF). If the patient experiences severe radicular symptoms due to cage protrusion, removal of the migrated cage is necessary. However, this procedure is sometimes very challenging because epidural adhesions and fibrous union can be present between the cage and vertebrae. We describe a novel classification and technique utilizing a navigated osteotome and the oblique lumbar interbody fusion at L5/S1 (OLIF51) technique to address this problem. Methods This retrospective study investigated consecutive patients with degenerative lumbar diseases who underwent TLIF/PLIF. Symptomatic cage migration was evaluated by direct examination, radiography, and/or computed tomography (CT) at 1, 3, 6, 12, and 24 months of follow-up. Cage migration/protrusion was defined as symptomatic cage protrusion > 5 mm from the posterior border of the over and underlying vertebral body compared with initial CT. We evaluated patient characteristics including body mass index, smoking history, fusion level, and cage type. A total of 113 patients underwent PLIF/TLIF (PLIF n = 30, TLIF n = 83), with a mean age of 71.1 years (range, 28–87 years). Mean duration of follow-up was 25 months (range, 12–47 months). Results Cage migration was identified in 5 of 113 patients (4.4%). All cases of symptomatic cage migration involved the L5/S1 level and the TLIF procedure. Risk factors for cage protrusion were age (younger), sex (male), and level (L5/S1). The mean duration to onset of cage protrusion was 3.2 months (range, 2–6 months). We applied a new classification for cage protrusion: type 1, only low back pain without new radicular symptoms; type 2, low back pain with minor radicular symptoms; or type 3, cauda equina syndrome and/or severe radicular symptoms. According to our classification, one patient was in type 1, three patients were in type 2, and one patient was in type 3. For all cases of cage migration, revision surgery was performed using a navigated high-speed burr and osteotome, and the patient in group 1 underwent additional PLIF without removal of the protruding cage. Three revision surgeries (group 2) involved removal of the protruding cage and PLIF, and one revision surgery (group 3) involved anterior removal of the cage and OLIF51 fusion. Conclusions The navigated high-speed burr, navigated osteotome, and OLIF51 technique appear very useful for removing a cage with fibrous union from the disc in patients with pseudarthrosis. This new technique makes revision surgery after cage migration much safer, and more effective. This technique also reduces the need for fluoroscopy.

Objective To analyze the clinical characteristics and survival prognosis of patients with AIDS-related malignant tumor. Methods We retrospectively analyzed the data of 354 patients with AIDS-related malignant tumor. Univariate analysis was conducted by Log rank test and multivariate analysis was conducted by Cox proportional risk regression model. Results The average age of the patients was 54.10±12.96 years old. The ratio of male to female patients was 2.1:1. The number of patients with AIDS complicated with lymphoma was the most, accounting for 28.25%. The 1-, 3- and 5-year survival rates were 78.48%, 62.13% and 55.31%, respectively. Univariate analysis showed that there were statistical differences in prognosis of patients with different types of malignant tumor, age, gender, medical insurance type, number of admissions after diagnosis of AIDS, average length of stay, radiotherapy or not, leaving hospital according to medical advice. Multivariate analysis showed that gender, number of admissions after diagnosis of AIDS, average length of stay, proportion of out-of-pocket and leaving hospital according to medical advice were independent risk factors affecting the survival and prognosis of patients. Conclusion AIDS is easily complicated with lymphoma, lung cancer and cervical cancer. The patients received insufficient anti-tumor courses in hospital.

The discourse of colonial and colonized conflicts is oriented in the form of resentment and hatred of the colonized community as part of the causality of traumatic events. The wounds of the past are then passed down through the concept of memory transmission both by famillial mechanism memory and affillial memory by first-generation to post-generation. It is this hereditary traumatic condition that contributes to maintaining the discourse of inferiority and binaryism between East and West. Thus, the purpose of this study is to describe the conflicts of colonizers and postcolonial colonizers as well as examine the efforts of Iksaka Banu to release these traumatic shackles through reconciliation and resistance efforts. This research method uses Teun van Critical Discourse Analysis (AWK). Dijk which is based on the analysis of the text dimension, the social cognition dimension, and the social context dimension. Data collection techniques in this study apply listening methods and advanced recording techniques, and document review techniques. The results showed that (1) A review of the dimensions of the text showed a reconstruction of the ambivalence and traumatic of Western subjects in the short stories of Iksaka Banu; (2) A study of the dimensions of social cognition shows that the reconstruction pattern of ambivalence and traumatic of the Western subject is used as Iksaka Banu's strategy to carry out traumatic reconciliation of colonized subjects as well as resistance to Western domination and hegemony; (3) A study of the social context shows two findings of the problem, First, the existence of social inequality over the mechanisms of Western domination and hegemony; Second, even so, Indonesian society is still confined by the problem of trauma while awareness of the subject's position on the condition of social reality cannot be managed as a potential resistance

C26H18BrN3O2, monoclinic, P21/n (no. 14), a = 9.5191(14) Å, b = 23.056(3) Å, c = 10.0556(15) Å, β = 95.470(3)°, V = 2196.9(6) Å3, Z = 4, Rgt(F) = 0.0640, wRref(F2) = 0.1645, T = 296(2) K.

Macroscopic examination, chemical composition analysis, metallographic structure, fracture scanning and element composition energy dispersive spectrum analysis were carried out on the cracked blade of the last stage of No.2 steam turbine unit in a thermal power plant. Results showed that the crack formation of turbine blades belonged to corrosion fatigue. The electrochemical corrosion of the blade was caused by corrosive media such as chlorine and sulfur in steam, and then intergranular stress corrosion cracking occurred under the centrifugal tensile stress, forming the crack source. Under the combined effect of corrosive medium, tensile stress and exciting force, the corrosion fatigue crack accelerated to expand and finally broke instantaneously.

MXene is a two-dimensional (2D) layered material composed of early transition metal carbides, nitrides and carbonitride. Due to MXene's unique layered morphology, high electrical conductivity, high specific surface area, excellent hydrophilicity and good thermal stability, it has broad application prospect in the fields of physics, materials, chemistry and nanotechnology. It can also be used in a variety of scientific fields such as catalysis, energy storage and sensors. This paper mainly reviews the research progress in electrochemical sensors based on MXene. Firstly, the principle, composition, electrode surface modification of electrochemical sensors and the preparation methods of MXene were introduced. Then, the research progress of MXene in electrochemical enzyme sensors, electrochemical non-enzyme sensors, electrochemical immunosensors, electrochemical aptamer sensors and electrochemical molecularly imprinted sensors were reviewed. Finally, the industrialization and commercialization of MXene electrochemical sensing field, and the challenges of the development of new types of MXene were pointed out. The applications of MXene in various analytes and more potential fields were also prospected.

Objective To test the function and evaluate the safety of the self-developed biosafety cage changing workbench. Methods According to the criteria of YY 0569-2011 "Class II Biological Safety Cabinet" and RB/T 199-2015 "Laboratory Equipment Biosafety Performance Evaluation Technical Specifications", we detected the various performance indicators of the cage changing workbench (HT-1303), which was independently developed and produced by Shenzhen Hongteng Biological Technology Co., LTD, and evaluated the safety and validity. Results The appearance integrity and stability of the main body of the biosafety cage changing workbench, the cleanliness of the working area, the velocity of the inflow airflow, the velocity of the descending airflow, the illuminance, the noise level, the airflow direction, the high-efficiency particulate air filter were at good condition, reaching the standards of level II biological safety cabinet. The airtightness of the contaminated goods recovery cabin and the sterilization chamber of utensil surface was good, but the size and quantity of the sterilized cage box need to be further improved. Conclusion The biosafety cage changing workbench developed by our team can be operated properly in whole. It can complete the replacement of individually ventilated cages in this workbench under negative pressure environment. Our workbench also can ensure the safety of operators, environment and experimental subjects.

ObjectiveTo detect the performance and use of class II biosafety cabinets in laboratories of veterinary-related research institutes.MethodsA total of 126 class II biological safety cabinetries being used by three veterinary-related reseatch institutes in Harbin were tested. The performance indicators were judged according to the test results and and analyze according to relevant standards, in order to understand the use of biological safety cabinets.ResultsThe overall pass rate of 126 biosafety cabinetries was 17.5%. The total qualified rate were 100%, 100%, 100%, 100%, 49.2%, 92.9%, 68.3%, 22.2% and 100% ,respectively in terms of the appearance of integrity, cleanliness of work area, integrity of high efficiency filter for supply and exhaust air, flow pattern, the velocity of inflow, the velocity of the downdraft, noise, illumination and alarm and interlock system of class II biosafety cabinet.ConclusionThe overall pass rate of biosafety cabinetries in some veterinary-related research institutes is low. Regular inspection, operation and maintenance management should be strengthened to eliminate biological safety hazard timely and prevent infection accidents of laboratory.

ObjectiveTo track and observe whether the long-term application of micro-electrolyzed sterile water system in laboratory animal barrier facilities can continuously maintain the terminal water aseptic.MethodsFrom April 2018 to March 2022, the microbiological detection of the micro-electrolyzed sterile water system had been tracked and monitored once each quarter in the barrier facilities of producing and breeding SPF grade rats and mice in Laboratory Animal Center of Sun Yat-sen University. Totally 8 sampling points were set, including one sampling point before the intake of the microelectrolytized water outlet into the water duct, six sampling points at the terminal water outlet, and one sampling point for the water return of the water network. Samples were taken according to aseptic operation procedures, and microelectrolysis aseptic water was detected according to the national standards GB 14925—2010 and GB/T 14926.41—2001.ResultsFrom April 2018 to March 2022, a total of 17 tests were conducted. During the normal operation of the micro-electrolyzed sterile water system, the quality of micro-electrolyzed water at 8 sampling points was sterile, in line with the national standard.ConclusionMicro-electrolyzed sterile water system can maintain the sterility of the terminal water supply, and can be used in laboratory animal barrier facilities for a long time.

This study is objected to develop a gas chromatographic-tandem mass spectrometric method to determine the contamination level of polychlorinated biphenyls, organochlorine pesticides and polybrominated biphenyl ether in wheat. In this method, the hydrated wheat powder was extracted with ethyl acetate and purified with acidic silica (44%). The gas chromatography-tandem mass spectrometry which operated on a dynamic multiple reaction monitor (dMRM) acquisition mode was using for instrumental analysis. The quantitation was carried out with internal standard method. The results demonstrated that all target analytes have good quantitative linear range with excellent regression factor (R2>0.996), while highly brominated biphenyl ethers were with quadratic regression. The recovery of method was between 57.9% to 118.6% with relative standard deviations of 1.6%~10.7%. The method detection limits were between 0.001 ng/g and 1.108 ng/g as the highly brominated biphenyl ether gave relatively poor detection limits. This method is simple, rapid, accurate and low-cost, especially useful for the high-throughput analysis of trace persistent organic pollutants in wheat.

Two microbial strains Bacillus subtilis HDJ1 and Bacillus velezensis HDJ2 were screened from soybean paste samples by corn gluten meal medium for high protease activity. Single factor fermentation experiment showed that the optimum conditions of liquid fermentation of corn gluten meal for strain HDJ1 were: fermentation temperature of 40 ℃, fermentation pH 8, inoculum of 6%, substrate concentration of 8%, rotating speed of 200 r/min, liquid-adding volume of 40 mL, fermentation time of 72 h; The optimum conditions for liquid fermentation of corn gluten meal for strain HDJ2 were: fermentation temperature of 40 ℃, fermentation pH 6, inoculum of 9%, substrate concentration of 8%, rotating speed of 150 r/min, liquid-adding volume of 120 mL, fermentation time of 72 h; The optimum conditions for the fermentation of corn gluten meal for equal combination of HDJ1 and HDJ2 were: fermentation temperature of 30 ℃, fermentation pH 8, inoculum amount of 6%, substrate concentration of 8%, rotating speed of 250 r/min, liquid-adding volume of 40 mL, fermentation time of 96 h. The results of Orthogonal test showed that the content of soluble protein of HDJ1, HDJ2, HDJ1 and HDJ2 was the highest when the fermentation temperature was 30 ℃, the fermentation pH was 8, the inoculum amount was 3%, the substrate concentration was 8%, therotation speed was 200 r/min, and the fermentation time was 96 h. The protease activity, soluble protein content and DPPH scavenging rate of the sample significantly increased after freeze-drying of the microbial fermentation, and the fermentation effect of the two combined stains was better than that of single strain.

Peptide receptor radionuclide therapy (PRRT) is one of the advanced therapies for neuroendocrine neoplasms (NENs), which can relieve the symptoms and improve the quality of life of patients with NENs with good tolerance to the treatment.However, since this treatment method has just started in China, how to implement standardized, efficient and high-quality nursing services for patients undergoing PRRT is still worth discussing. By referring to related international guidelines and clinical nursing standards, and combining our experience in the treatment of NENs using 177Lu-DOTATATE, we proposed the key nursing points during the treatment process, and elaborated how to prevent common adverse reactions and undergo psychological intervention, in hope of the related personnel being able to provide more safe treatment and to improve nursing security.

Compared with single-sided welding, double-sided welding can melt through thicker workpieces and improve the mechanical performance of the weld. In this work, laser welding with filler wire of 2195 Al–Li alloy plates is conducted via double-sided out-of-sync welding. By combining experiment and numerical simulation results, the influence laws of the weld’s mechanical properties are studied by considering the condition of both sides under different welding parameters. The results show that the welding speed is the key parameter determining the heat input of the weld. In the welds fabricated at slow welding speeds, the cooling rate is greater, resulting in accelerated solidification. The weld solidifies before hydrogen overflows from the weld pool, resulting in increased pore density and weakened mechanical properties. Therefore, welding parameters determine the heat input of the weld and subsequently the mechanical properties. It is shown that a special double-sided welding strategy can effectively control the heat input. Specifically, in contrast to those of the first, the welding parameters of the second side of the weld reduce the wire feeding speed when other parameters are held constant. Compared with the process strategy using identical double-sided parameters, this can slightly increase the heat input and reduce the defects in the weld, which can improve its mechanical properties. In the comparative experiment, the wire feeding speed was reduced from 5 to 3 mm·s−1, and the tensile strength of the weld was increased by 10%.

Increased expression of membrane type 1-matrix metalloproteinase (MT1-MMP/MMP14) is associated with the development of many cancers. MT1-MMP may promote the entry of yes-associated protein1 (YAP1) into the nucleus by regulating the regulation of β1-integrin. The purpose of this study was to investigate the effects of MT1-MMP, β1-integrin and YAP1 on the prognosis of gliomas. The expression of proteins was detected by bioinformatics and immunohistochemistry. The relationship between three proteins and clinicopathological parameters was analyzed by the χ 2 test. Survival analysis was used to investigate the effects of three proteins on prognosis. The results showed that high expressions of MT1-MMP, β1-integrin and YAP1 were found in glioblastoma (GBM) compared with lower-grade glioma (LGG). There was a significantly positive correlation between MT1-MMP and β1-integrin (r = 0.387), MT1-MMP and YAP1 (r = 0.443), β1-integrin and YAP1 (r = 0.348). Survival analysis showed that patients with overexpression of MT1-MMP, β1-integrin and YAP1 had a worse prognosis. YAP1 expression was the independent prognostic factor for progression-free survival (PFS). There was a statistical correlation between the expression of MT1-MMP and YAP1 and isocitrate dehydrogenase 1 (IDHl) mutation. Thus, this study suggested that MT1-MMP, β1-integrin and YAP1, as tumor suppressors, are expected to be promising prognostic biomarkers and therapeutic targets for glioma patients.

Objective To explore the application value of multi ⁃ modal image fusion three ⁃ dimensional (3D) reconstruction technology in operation of meningioma in the central area. Methods and Results Using multi⁃modal image fusion 3D reconstruction technology to study 46 patients admitted to The First Affiliated Hospital of University of Science and Technology of China from April 2019 to May 2021. 3D Slicer software was used to process the original imaging data to reconstruct 3D models of tumor, peritumoral vein, cerebral cortex, skull, scalp, etc., and intraoperatively Sina software was used for projection assisted incision design to verify the actual tumor position and its adjacency structures preoperatively. To reconstruct the effect before surgery, the tumor was removed under microscopy. All patients completed the preoperative reconstruction. The intraoperative verification showed that the tumor and its adjacency structures were in good agreement with the preoperative 3D model. All patients did not cause unnecessary injury due to insufficient preoperative exposure caused by improper preoperative planning. Forty⁃six cases of meningioma in the central area were completely removed under the microscopy, 32 cases had no limb dysfunction, 8 cases had significant improvement in limb function, and 6 cases had decreased muscle strength. None of the patients had epileptic seizures. One patient had postoperative infection, after active anti⁃infection, he was cured and discharged. There was no death. Conclusions The 3D Slicer reconstruction technology applied to meningioma in the central area can display the tumor adjacent structures in a intuitive, multi-dimensional and dynamic 3D manner, guide the maximum resection of the tumor and protect the peritumoral vein and cortex during the operation. Sina software has clinical and practical value in preoperative positioning of meningioma in the central area, such as accuracy, safety, non-invasiveness, and convenience, and it is worthy of further research and promotion.

An anal fistula is an external abnormal anatomical connection between the rectum and the outer skin of the anus. Symptoms include anorectal pain, abscesses, perianal cellulitis, smelly or bloody drainage of pus, and, in some cases, difficulty controlling bowel movements. Diagnosis and evaluation of anal fistulas is crucial for prognosis and for the choice of the treatment method. In this study, we aimed to discover potential biomarkers from serum proteins for the prediction of anal fistulas.

In order to study the complex transient flow characteristics of a high-pressure aero-fuel centrifugal pump within its full working envelope, a certain type of centrifugal pump is numerically simulated, in which the simulation results are compared with the experiment results to verify the effectiveness of the present simulation method. Then, the verified simulation method is selected to analyze the transient flow characteristics, in which the time-frequency characteristic of pressure pulsation at monitored positions is analyzed by using fast fourier transform. In addition, the unsteady flow structures are studied by focusing on the relative speed, turbulent kinetic energy and so on. The results show that the main frequency of pressure pulsation in the impeller and volute is rotation frequency and blade frequency, respectively, where different monitoring points show similar trend. Meanwhile, the flow is relatively stable under design flow rate condition. However, a certain large-scale vortex appears in the impeller channel under small flow rate conditions, which mainly exists at the exit of the impeller channel near the tongue. In addition, turbulent kinetic energy at the exit of the impeller and the tongue has a large distribution range and changes seriously, where a certain hydraulic loss is produced.

The paper studies the power measurement methods of the operating power grids with various types of harmonics and inter-harmonics and gives a relatively complete solution， which sums up and integrates a variety of power and energy measurement methods， forming a universal power calculation theory. The simulation results show that this solution can not only achieve accurate measurement of active power and reactive power based on frequency-adaptive technology， but also obtain the power distribution of the fundamental wave and each harmonic， helping harmonic source identification， reactive power compensation， control of system parameters and improvement of power quality.

Renewable biomass resources have become increasingly attractive in recent years. In this study, the pyrolysis of waste navel orange peels was carried out with different metal oxides (Cu2O, CaO, V2O5, Fe2O3, and ZnO) in a tube furnace to obtain high-quality bio-oil, from which high-value chemicals such as 3-furaldehyde could be well recovered to enhance the economic value of waste navel orange peels. The effects of different metal oxides on bio-oil were analyzed by GC/MS. The results showed that Cu2O and Fe2O3, as catalysts for slow pyrolysis, promoted the production of 3-furaldehyde compounds at a scale of approximately 5.69 and 4.82 times higher than that of pyrolysis without the addition of metal oxides, respectively. High-value chemicals such as 3-furaldehyde obtained from bio-oil can enhance the economic value of waste navel orange peels for full recovery and reuse.

SiC foam ceramics are extensively used in numerous industrial applications that require high-temperature conditions. They can be used as thermal insulation, structural catalyst supports and energy storage materials. In this article, effective thermal conductivity of SiC foam ceramics at high temperature is studied by steady plane heat source method. This research aims to investigate the variations of effective thermal conductivity with pore density, stacking thickness, heat source temperature, and pore arrangement structure of foam ceramics. By a comparison of effective thermal conductivities of various pore density ceramic sheets, the experimental results show that the effective thermal conductivity of foam ceramics decreases with the increase of the pore density and stacking thickness. The effective thermal conductivity of the foam ceramics increases significantly when the heat source temperature is more than 200°C. For modular SiC foam ceramics, increasing the average pore density and sudden change of the pore density between ceramic sheets are not conducive to the increase of the effective thermal conductivity.

Ce and F were added to MCM-48 molecular sieve by hydrothermal synthesis, and Pd/Ce(F)-MCM-48 metal acid bifunctional catalysts were prepared by impregnation method. The physical and chemical properties of Ce(F)-MCM-48 and Pd/Ce(F)-MCM-48 were characterized by X-ray diffraction, scanning electron microscope, NH3 temperature programmed desorption instrument, Fourier infrared spectrometer, and X-ray photoelectronic spectrometer characterization methods. The results showed that when the molar ratio of the raw materials was n(Ce):n(TEOS) = 0.02 and n(NaF):n(TEOS) = 0.10, Ce(F)-MCM-48-0.10 molecular sieve had a high degree of order and large specific surface area and pore volume, the total acid content increased, and the acid strength also increased. And it had an acidic center and generated certain oxygen vacancies. The catalyst prepared after Pd impregnation had good dispersibility. 0.4% Pd/Ce(F)-MCM-48-0.10 catalyst still maintained the crystalline phase of MCM-48 molecular sieve. A micro-reaction device was used to examine the catalytic performance of n-heptane isomerization of Pd/Ce(F)-MCM-48-0.10 catalysts. When the hydrogen flow rate was 30 mL·min−1, reduction temperature was 300°C, reduction time was 4 h, weight hourly space velocity was 7.6 h−1, and reaction temperature was 280°C, 0.4% Pd/Ce(F)-MCM-48-0.10 catalyst was used in the heptane isomerization reaction, where the conversion of n-heptane was 67.3% and the selectivity of isoheptane was 96.5%.

Prostate cancer (PCa) is a common type of cancer worldwide. The incidence of PCa increases with age and it is the most common malignant tumor in men. Tissue biopsy and the serum prostate-specific antigen are still the standards for diagnosing suspected PCa. Long non-coding RNA (lncRNA) contributes to the progression of PCa by recruiting transcriptional regulators. We utilized high-throughput sequencing data and bioinformatics analysis to identify specifically expressed lncRNAs in PCa and filtered out three specific lncRNAs for further analysis: AC077690.1, AL049874.3 and AP001037.1. We constructed a lncRNA regulatory network and used differentially expressed mRNA interactions to predict the functions of the selected lncRNAs. Functional enrichment analysis and PCR verification of these three lncRNAs revealed that they were closely related to well-known PI3K-Akt-mTOR and the forkhead box protein (FOXO) signaling pathways involved in PCa. By understanding the related interactions between these molecules and signaling pathways, the lncRNAs could be potential candidates for therapeutic targets in PCa.

4, 4'-diaminodiphenyl ether (ODA) and pyromellitic dianhydride (PMDA) were used as monomers. Carbon nanofiber (CNF) was used as the reinforcing agent. CNF reinforced polyimide (PI) composite aerogels were prepared with acidified CNF (a-CNF) via sol-gel process followed by freeze-drying technology. The morphologies, thermal insulation, microwave absorption as well as compression properties of PI composite aerogels were characterized. The results show that the volume of PI composite aerogels is shrunk from 45.52% to 35.32%, and the density is decreased from 0.084 g/cm3 to 0.069 g/cm3 with the increase of a-CNF content. The composite aerogels exhibit bigger pore sizes and wider pore size distribution after the introduction of a-CNF as well. CNF in PI matrix play roles for reducing the shrinkage of PI composite aerogels, thereby the thermal conductivity is reduced. Additionally, the reflection loss (RL) of PI composite aerogel with 15%(mass fraction) of a-CNF (15% CNF/PI) reaches -9.7 dB at 8.3 GHz. This is due to the fact that the introduction of CNF induced the conduction loss and the porous structure of aerogels provides better impedance matching. The compressive strength and modulus of PI composite aerogels with 15% of a-CNF content are increased by approximately 1.5 times and 2 times compared with pure PI aerogel, respectively.

Estimating the flying attitude of the missile body during flight is vitally important for the intelligent ammunition. The earlier and more accurate the posture information is obtained, the more conducive it is to the control process of the intelligent ammunition. The magnetometer is commonly used to measure the roll attitude of the missile. However, the cumbersome calibration steps and noise interference of the missile usually cause the delay in the attitude calculation and inaccurate measurement. To solve these issues, an adaptive reconfigurable unscented Kalman filter (ARUKF) method based on energy estimation is proposed. The magnetic field measured by the magnetometer is analyzed in real time based on the roll characteristic of the intelligent ammunition to achieve the initial calibration of the magnetometer parameters. With the obtained calibrated parameters, the filter state variables are estimated by establishing the residual estimation function in the UKF, which guides the reconstruction of the UKF to minimize the computational cost of the attitude estimation process. Simultaneously, the on-board computer system feeds back the action of the rudder system in real time to guide the configuration of the noise parameters in the UKF process, which can effectively reduce the interference of the magnetic field generated by the rudder system on the attitude estimation. The numerical simulation and experiments show that the proposed method performs better in terms of parameter convergence speed and estimation accuracy, compared with the traditional UKF method, which has great application prospect in the field of intelligent ammunition.

An experimental study is conducted to find the characteristics of steam plume and pressure oscillation on direct contact condensation by a side-hole sparger. Synchronal measuring of transient pressure of the steam plume is gained from the high-speed camera and high-pressure sensor respectively. The influence of steam mass flux and water temperature on direct contact condensation characteristic are presented and its regime map is plotted. Then, the dynamic connections of transient pressure and steam plume in different condensation regimes are analyzed. It is found that high frequency pressure oscillation and the collapse of detached bubbles occur at the same time. Together with the condensing and disappearing process of the collapse of detached bubbles, the intensity of pressure oscillation decays exponentially in a vibration way. The changing trends of steam plume length in condensation oscillation regime and stable condensation regime are also obtained, which shows that the steam plume increases with the steam mass flux and the temperature in the condensation oscillation regime. When entering the stable condensation regime, the steam plume suddenly decreases and then increases with the temperature and the steam mass flux. The research results are useful for the engineering application of sparger in steam emission devices.