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We propose a full discretization to approximate the invariant measure numerically for parabolic stochastic partial differential equations (SPDEs) with non-globally Lipschitz coefficients. We present a priori estimates and regularity estimates of the numerical solution via a variational approach and Malliavin calculus. Under certain hypotheses, we present the time-independent regularity estimates for the corresponding Kolmogorov equation and the time-independent weak convergence analysis for the full discretization. Furthermore, we show that the V-uniformly ergodic invariant measure of the original system is approximated by this full discretization with weak convergence rate. Numerical experiments verify theoretical findings.

To present a radiographic follow-up study of the use of a nonvascularized iliac crest bone graft as a treatment for modified Blauth type IIIB thumb hypoplasia.From January 2015 to December 2019, nonvascularized iliac crest bone grafts were used to reconstruct the first metacarpal in 23 cases with type IIIB thumbs. The average follow-up duration was 1.9 years (range 1.0-3.9 years). We evaluated the patients' serial x-rays and measured the width and length changes of the reconstructed first metacarpals.Survival of the graft, judged radiographically, was achieved in 20 cases (20/23, 87%), with an average reduction of 33% in the width of the graft. Shortening of the graft (average 2.3 mm, range 0.1-5.6 mm) was noted in 11 of the 20 cases, and an increase in the length of the graft (average 4.2 mm, range 0.7-8.6 mm) was observed in the other 9. Bone graft failure (3/23, 13%) occurred in 3 cases because of significant bone resorption.For type IIIB thumb hypoplasia, a nonvascularized iliac crest bone graft was a feasible method to reconstruct the first metacarpal, with a 13% risk of graft failure, 33% average reduction in graft width, and 55% reduction in graft length. However, in cultures that value the preservation of a 5-digit hand, this technique may provide an alternative to excision with index pollicization.Therapeutic IV.

Toll-like receptor 4, a highly conserved protein of innate immunity, is responsible for the regulation and maintenance of homeostasis. It has been implicated in the progression of ulcerative colitis (UC) by interacting with its downstream pathway myeloid differentiation factor 88 (MyD88) and nuclear factor kappa B (NF-κB). This study aimed to evaluate the effect of a specific inhibitor of toll-like receptor 4, TLR4-IN-C34 on gut microbiota to elucidate its mechanism in UC mice. Dextran sulfate sodium significantly induced weight loss, diarrhea and rectal bleeding, and colonic damage in mice, which occurred concomitant with dysbiosis of intestinal flora. Intestinal dysbiosis were partially ameliorated by TLR4-IN-C34. Meanwhile, a reduction in inflammatory cell infiltration, enhanced antioxidant activity in colon tissues, and reconstruction of intestinal barrier were observed in mice administrated with TLR4-IN-C34. MyD88 and NF-κB were significantly reduced after TLR4-IN-C34 treatment. MyD88

This paper investigates the finite-time stability (FTS) and finite-time stabilization for a class of nonlinear singular time-delay Hamiltonian systems, and proposes a number of new results on these issues. Firstly, an equivalent form is obtained for the nonlinear singular time-delay Hamiltonian systems by the singular matrix decomposition method, based on which some delay-independent and delay-dependent conditions on the FTS are derived for the systems by constructing a kind of novel Lyapunov function. Secondly, we use the equivalent form as well as the energy shaping plus damping injection technique to investigate the finite-time stabilization problem for a class of nonlinear singular port-controlled Hamiltonian (PCH) systems with time delay, and present a specific control design procedure for the systems. Finally, we give several illustrative examples to show the effectiveness of the results obtained in this paper.

Nocardia spp. is a pathogen responsible for a variety of clinical infections, ranging from skin and soft tissue infections, to the respiratory tract and central nervous system infections. Its epidemiological characteristics, including species distribution, clinical features, and antimicrobial susceptibility profiles, should be under surveillance for the prevention and treatment of nocardiosis. In the present study, over a 9-year period (from 2009 to 2017), 53 non-repetitive Nocardia isolates were collected from 8 tertiary general hospitals of 7 cities in China. These isolates were identified to species level by multilocus sequence analysis(MLSA). The clinical data were also reviewed. The susceptibilities to 10 commonly-used antibiotics for Nocardia were determined by E-test stripes, and the resistance rates, MIC50 and MIC90 to each antibiotic by different species were analyzed. Of 53 Nocardia isolates, N. farcinica was the most common species (24.5%, 13/53), followed by N. cyriacigeorgica (20.8%, 11/53), N. terpenica (15.1%, 8/53), N. abscessus (9.43%, 5/53), N. otitidiscaviarum (7.55%, 4/53), respectively. Furthermore, 31 Nocardia (58.5%) isolates were recovered from lower respiratory tract (sputum and BALF), 15 (28.3%) from superficial Infection, 3 (5.7%) from pleural effusion, 2 (3.8%) from CSF, and 1 from bone marrow and 1 from synovial fluid, respectively. The antibiotic resistance profiles varied between different Nocardia species. All Nocardia isolates were susceptible to linezolid, followed by imipenem and amikacin (both 92.5% susceptibility rate). N. terpenica, rarely documented elsewhere, showed a different antimicrobial susceptibility profile. In summary, herein, the clinical and antibiotic resistance features of Nocardia species reported would be helpful for understanding the diversity of Nocardia species circulating in China and for decision making in the context of empiric therapy.

In this study, an efficient route was developed to prepare high quality erionite (ERI) zeolite by hydrothermal conversion of faujasite (FAU) zeolite as an aluminosilicate source in the presence of N,N-dimethylpiperidinium hydroxide (DMPOH). Pure ERI zeolite was successfully synthesized within only 8 h by carefully controlling the alkalinity (OH−/SiO2) of the initial gel and the proportion of DMP+ and K+. Compared with the conventional ERI zeolite synthesized via a Charge Density Mismatch method, the FAU-derived ERI zeolites show superior properties such as higher crystallinity, smaller crystal size, larger micropore volume and better hydrothermal stability. In addition, catalytic test in the ethanol dehydration reaction shows that the ERI zeolites obtained from FAU exhibit extraordinary performances to those of the conventional one. Finally, crystallization process from FAU to ERI was investigated in detail by UV Raman and XRD. The results show that the framework of ERI zeolite is formed by rearrangement of 4-rings generated from the initial FAU zeolite.

This paper investigates the finite-time robust control problem of a class of nonlinear time-delay systems with general form, and proposes some new delay-independent and delay-dependent conditions on the issue. First, by developing an equivalent form, the paper studies finite-time stabilization problem, and presents some delay-dependent stabilization results by constructing suitable Lyapunov functionals. Then, based on the stabilization results, we study the finite-time robust control problem for the systems, and give a robust control design procedure. Finally, the study of two illustrative examples shows that the results obtained of the paper work well in the finite-time stabilization and robust stabilization for the systems. It is shown that, by using the method in the paper, the obtained results do not contain delay terms, which can avoid solving nonlinear mixed matrix inequalities and reduce effectively computational burden. Moreover, different from existing finite-time results, the paper also presents delay-dependent sufficient conditions on the finite-time control problem for the systems.

IM-5 zeolite was modified with different amounts of phosphorus species. The effect of the introduction of phosphorus into IM-5 zeolite (P-IM-5) was evaluated on the alkylation of toluene with methanol. The samples were characterized by X-ray diffraction, scanning electron microscopy, N2 physical adsorption, 31P magic angle spinning nuclear magnetic resonance, inductively coupled plasma optical emission spectroscopy, temperature-programmed desorption of ammonia, Fourier transform infrared spectra of pyridine, 2,6-di-tert-butyl-pyridine and 2,6-lutidine adsorption, and thermogravimetric analysis after reaction. The results showed that the zeolite structure was not changed, but the total amount of acid sites decreased with increasing phosphorus loading. The phosphorus-modified IM-5 samples exhibited much higher stability on the alkylation of toluene with methanol than the parent zeolite and the optimal phosphorus amount added was 0.5 wt %. The excellent catalytic performance could be ascribed to the low ratio of B/L acid sites upon phosphorus modification, which suppressed coke formation.

Background: Gynecological and reproductive problems that arise during childhood and adolescence can have a significant impact on individuals, families and society, and they are increasingly recognized as a public health priority. Methods: We conducted a retrospective study based on the electronic medical records of 207,287 gynecological visits over a period of 13 years (January 2006 to December 2018) at the Department of Pediatric and Adolescent Gynecology of The Children’s Hospital, Zhejiang University Medical School. The final analyses included 97,252 patients with gynecological problems. Additionally, we conducted a systematic review focused on previous studies examining PAG problems in China. Findings: The number of first-visit PAG patients increased from 4,582 to 11,876 during 2006-2018. Overall, genital inflammation was the most common presentation (57·0%), followed by early puberty (18·2%) and consultation of growth and development (10·2%). The proportion of other problems such as gynecological examination, menstrual disorder, other endocrine problems, genital trauma, masturbation syndrome, anomalies of the genital tract, and genital tumor, ranged from 0·5% to 5·6%. The disease pattern varied across age groups: among the 0-6 age group, over 78·0% had genital inflammation; for the 7-9 age group, genital inflammation and early puberty accounted for 43·4% and 39·6% of the cases, respectively; for ages 10-18, the most common problems were consultation of growth and development (34·9%), genital inflammation (21·4%), and menstrual disorder (20·7%). Twenty-two studies analyzing patterns of PAG issues in outpatient settings in China were included in the systematic review, showing an average weighted percentage of 48·8% for genital inflammation and 25·2% for menstrual disorder. Interpretation: Genital inflammation was the most common issue for pediatric and adolescent patients with gynecological problems. Other common issues included early puberty for children and teenagers, and consultation of growth and development and menstrual disorder for adolescents. Funding: The National Nature Science Foundation of Zhejiang (LQ18H040001, LY20H040011) Medical Scientific Projects from Health department of Zhejiang Province(2017KY101). Declaration of interests: The authors report no conflict of interests. Ethical Approval: The study was approved by the Human Subjects Committees of the Children’s Hospital, Zhejiang University School of Medicine.

The sorption of five potent endocrine disruptors as representative hydrophobic organic contaminants (HOCs) namely estrone (E1), 17β-estradiol (E2), estriol (E3), 17α-ethynylestradiol (EE2) and bisphenol A (BPA) on functionalized biochar (fBC) was systematically examined, with a particular focus on the importance of π-electron-donor (phenanthrene: PHEN) and π-electron-acceptors (1,3-dinitrobenzene: DNB, p-amino benzoic acid: PABA) on sorption. Experimental results suggested that hydrogen-bond formation and π-π-electron-donor-acceptor (EDA) interactions were the dominant sorption mechanisms. The sorption of HOCs decreased as E1 > E2 > EE2 > E3 > BPA based on the Freundlich and Polanyi-Mane-models. The comparison of adsorption coefficient (Kd) normalized against hexadecane-water partition coefficient (KHW) between HOCs and PHEN indicated strong π-π-EDA interactions. π-π interactions among DNB, PHEN and HOCs were verified by the observed upfield frequency (Hz) shifts using proton nuclear magnetic resonance (1H NMR) which identified the specific direction of π-π interactions. UV–vis spectra showed charge-transfer bands for π-donors (PHEN and HOCs) with the model π-acceptor (DNB) also demonstrating the role of π-π EDA interactions. The role of π-electron-donor and π-electron-acceptor domains in fBC was identified at different solution pH.

This paper investigates the finite-time control problems for a class of discrete-time nonlinear singular systems via state undecomposed method. Firstly, the finite-time stabilization problem is discussed for the system under state feedback, and a finite-time stabilization controller is obtained. Then, based on which, the finite-time H∞ boundedness problem is studied for the system with exogenous disturbances. Finally, an example of population distribution model is presented to illustrate the validity of the proposed controller. Because there is no any constraint for singular matrix E in the paper, controllers can be designed for more discrete-time nonlinear singular systems.

When compared with conventional gas field development, the coalbed methane (CBM) production process has its unique features that the produced natural gas contains saturated vapor and the gathering system is characterized as two-phase flow and liquid drainage. This paper aims to compare the drainage measures for draining liquid that condenses from wet CBM and transported in surficial gathering pipeline network. The unsteady non-fully developed flow of wet CBM in dendritic gathering and transmission pipeline network was simulated and analyzed. Phase change of water vapor was presented during the low-liquid loading flow and heat transfer process. The mass flow rate in pipeline network was supposed to increase continuously due to the aggregation and accumulation of liquid. The pressure at some adjacent nodes was validated by experimental data in situ. Three measurements for draining liquid are proposed, which include pigging, installing devices and cooling fluid at pipe inlet. It is concluded that the optimal strategy is combining the pigging method with installing several drainage devices rather than only pigging or the combination of pigging and cooling. Additionally, the presented model is a worthy way to optimize the pigging cycle to ensure the high efficient operation for the pipeline. Therefore, this paper provides a safe and economic method for the flow assurance of wet CBM fields.

Oil-water two phase stratified wavy pipe flow widely exits in the petroleum and chemical industries. When the temperature of the oil is below abnormal point, the oil phase acts as non-Newtonian behavior and the flow process becomes more complex. A coupling mathematical model of oil-water non-Newtonian stratified wavy pipe flow under non-isothermal condition is established in bipolar coordinate system with the consideration of the fluctuation at the oil-water interface. The pressure gradients calculated are validated by the results from literature and the relative errors are within 6%. Then the oil-water non-Newtonian two-phase stratified wavy pipe flow process is simulated in this paper. The bulk temperature and pressure drop along the pipeline can be predicted by the models. Temperature and velocity distribution at the different pipe cross sections are simulated and analyzed in detail. The non-Newtonian behavior of oil phase and the effective roughness of oil-water interface can also be obtained from the model. Moreover, the non-dimensional parameter analysis is used to research the mechanisms of flow and heat transfer. Thus, the numerical model can be widely applied to calculate the global fluid properties and other operating parameters which are useful for the management of oil-water mixing transportation pipelines.

The accumulation of defects and internal stresses and related changes of the direct and reverse martensitic transition (MT) on thermocycling over the phase transition in different Fe–Mn–Si alloys are investigated by in situ neutron diffraction, TEM, SEM-EBSD, DSC and mechanical spectroscopy. The temperature of direct MT in Fe-22Mn-3Si, Fe-26Mn-4Si and Fe-26Mn-7Si alloys decreases during thermal cycling, while that of the inverse MT increases, which causes a widening of the transformation hysteresis. Transmission electron microscopy shows that a large number of dislocations and stacking faults are formed in both martensitic and austenitic phases in the Fe-22Mn-3Si annealed alloy submitted to γ ↔ e thermocycling. From in situ neutron diffraction tests on Fe-22Mn-3Si annealed alloy and classical Williamson-Hall analysis, we found that the microstrains in the e-martensite after 1 and 12 thermocycles are roughly twice higher as compared with the austenite phase.

Ammonia is a vital component of the nitrogen (N) cycle of terrestrial ecosystems in terms of volatilization and deposition. Here, a field experiment was undertaken to simultaneously investigate the effects of rice straw and urea incorporation on ammonia volatilization, atmospheric N deposition, yields and agronomic nitrogen use efficiency (NUE) under a rice-wheat system in China. The experiment involved four treatments: control (0 N, 0 straw), NS0 (250 kg N ha−1 season−1, 0 straw), NS1 (250 kg N ha−1 season−1, 3 t ha−1 yr−1 straw), and NS2 (250 kg N ha−1 season−1, 6 t ha−1 yr−1 straw) in the rice-wheat annual rotation system. The results indicated that the NS0, NS1 and NS2 treatments emitted cumulative ammonia of 14.0%, 16.4%, and 19.2%, respectively in the rice season and 7.6%, 11.1%, and 12.3%, respectively in the wheat season among the total urea-N application. Compared to the NS0 treatment, the NS1 and NS2 treatments significantly increased the cumulative ammonia emissions by 15.5% (p

A series of hierarchical ZnSAPO-34 zeolites were synthesized by treatment with different concentrations of tetraethylammonium hydroxide (TEAOH) solutions. The synthesized samples were characterized by X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), inductively coupled plasma optical emission spectroscopy (ICP-OES), temperature-programmed desorption, Fourier transform infrared, and N2 adsorption and desorption techniques and studied as catalysts for the methanol to olefin reaction. The characterization results reveal that the crystal size of ZnSAPO-34 is greatly reduced compared with the parent SAPO-34 owing to the incorporation of Zn. Hierarchical pores with the sizes up to the macropore level in the ZnSAPO-34 zeolites are created with the post-treatment of TEAOH. The acid strength and the amounts of the strong acid of the hierarchical ZnSAPO-34 zeolites decrease after the post-treatment because TEAOH preferentially extracts Si species from the zeolite. The hierarchical ZnSAPO-34 zeolites exhibit superior catalytic performance than that of the parent ZnSAPO-34, owing to the shortened transportation distance and the appropriate acidity of the treated samples.

A nonlinear controller design method based on quarter-car model of semi-active suspension is proposed for input constraints problem. Taking the system nonlinear characteristics and input constraints into account sufficiently, an auxiliary system is introduced to combine backstepping method to cut down vibration of semi-active suspension. In the design process, we use a Nussbaum function to compensate for the nonlinear term arising from the input constraints. Due to the absence of any linearization method, the control input is limited to a certain range while maintaining the nonlinear characteristics of the system. The simulation results show that the suspension system can move toward stability quickly in the condition of input saturation, and can effectively improve the ride quality of the vehicle.

The effect of partial substitution of Cu by Cr on the spinodal decomposition of face-centered cubic (f.c.c.) austenite in the as-quenched Mn-10Cu-4Cr alloy is studied after different ageing treatments by small-angle neutron scattering (SANS) and in situ neutron diffraction. Under the same quenching conditions, additional α-Mn phase with A12 structure in the Mn-10Cu-4Cr alloy is observed as compared with Mn-13Cu alloy at room temperature (RT). The replacement of Cu atoms by Cr atoms retards the spinodal decomposition of austenite during ageing compared to the binary Mn-13Cu alloy according to SANS and Differential scanning calorimetry (DSC) results. The reason is that Cr enriches in the α-Mn phase, and thus its addition leads to the formation of the α-Mn phase. Compared to the Mn-13Cu alloy, there is an increase in the tetragonality of the face-centered tetragonal (f.c.t.) martensite, which may be attributed to changes in magnetic interaction owing to partial substitution of Cu by Cr. The higher tetragonality value leads to a higher volume effect during martensitic transition (MT) of Mn-10Cu-4Cr alloy than that of Mn-13Cu alloy (around 1.5 times). The lattice parameters of the f.c.t.-martensite do not converge exactly to the parameter of the f.c.c.-austenite at the MT temperature due to replacement of Cu by Cr. Instead, there is a jump of the lattice parameters during phase transition.

The laser-induced breakdown spectroscopy (LIBS) approach has been used to ex-situ measure the deuterium (D) retention and carbon (C) deposition on the surface of tungsten (W) castellated blocks adopted from the Korea Superconducting Tokamak Advanced Research (KSTAR). The well-resolved D∖H spectra with a high signal to noise ratio (S/N) up to 500 has been achieved.The lateral distributions of the deposited C and detained D on the three different shaped divertor blocks (Rounded, Chamfered, Double chamfered) were investigated. The depth of the deposited C layer was also measured as ∼200 nm to ∼650 nm based on the spectral line intensity using a self-defined function approach. It was found that the edge shape strongly affects the C and D distribution features, which are dependent on the particle and heat flux arriving on the related area. The features of C and D deposition and their distributions on the different shaped blocks provide valuable information for the theoretical model on plasma-wall interaction. This indicates that LIBS has a unique potential for the diagnosis of impurity deposition and fuel retention in KSTAR or related fusion devices.

Study Objective In this study we investigated the sonographic features of vaginal foreign bodies in girls and the diagnostic role of combined transperineal and transabdominal ultrasonography in the detection of vaginal foreign bodies in this population. Design, Setting, Participants, Interventions, and Main Outcome Measures A retrospective review of the records of 249 girls seen in the outpatient pediatric and adolescent gynecology clinic of our hospital and referred to our department for sonographic evaluation of suspected vaginal foreign bodies between 2013 and 2016 was performed. All patients were transperineally and transabdominally scanned using an ultrasound machine with 3-MHz and 7.5-MHz transducers. The sonographic features of the detected foreign bodies were recorded and reported. All patients also underwent pelvic radiography. The presence of foreign bodies was confirmed using vaginoscopy. Results Two hundred forty-nine patients were included in this study, and vaginal foreign bodies were detected in 181 patients. Vaginal foreign bodies often present in girls aged from 2 to 12 years old. The most common vaginal foreign bodies were toilet paper, beads, small parts of toys, cap of water color brush, and crayons. The overall sensitivity, specificity, positive and negative predictive values of transperineal/transabdominal sonography in the diagnosis of vaginal foreign bodies were 81%, 53%, 82%, and 51%, respectively. The sensitivity, specificity, and positive and negative predictive values of transabdominal sonography were 33%, 49%, 63%, and 21%, respectively. The sensitivity, specificity, and positive and negative predictive values of transperineal sonography were 64%, 49%, 77%, and 33%, respectively. Abnormal findings were detected using x-ray in only 43 of the 181 cases (23.7%). The sensitivity, specificity, and positive and negative predictive values of x-ray were 24%, 91%, 88%, and 31%, respectively. The size of the foreign bodies ranged from 2 mm to 35 mm. For foreign bodies larger than 5 mm, the rate of sonographic accuracy reached 100%. For foreign bodies smaller than 5 mm, 32 false positive results, and 34 false negative results were identified. One hundred thirty-nine of 181 foreign bodies were less than 2 cm from the vaginal orifice (77%). All foreign bodies were hyperechoic compared with adjacent tissues. Some vaginal foreign bodies had characteristic echo patterns. With the exception of 1 patient with a detained AAA battery that caused vaginal ulceration, the other patients had a full recovery. Conclusion Vaginal foreign bodies were hyperechoic compared with adjacent tissues and often had characteristic echo patterns. The use of combined transperineal and transabdominal ultrasonography might be helpful in diagnosing foreign bodies, especially when the size of the foreign body is larger than 5 mm. Therefore, ultrasonography might be preferred for the initial evaluation of suspected vaginal foreign bodies, because it is a noninvasive, radiation-free, and inexpensive technique.

When the natural gas with vapor is flowing in production pipeline, condensation occurs and leads to serious problems such as condensed liquid accumulation, pressure and flow rate fluctuations, and pipeline blockage or corrosion. The motivation is to study phase change of vapor and liquid level change during the condensing process of water-bearing natural gas characterized by coupled hydro-thermal transition and phase change process. A hydro-thermal-mass transfer coupling model is established to investigate the mechanisms and effects of the condensation on the gas-liquid two-phase wavy flow in production pipelines. The bipolar coordinate system is utilized to obtain a rectangular calculation domain. An adaptive meshing method is developed to automatically refine the grid near the wavy gas-liquid interface which is moving continuously. Large eddy simulation model is used to calculate turbulent viscosity. The pressure gradient, liquid holdup, velocity distribution, shear stress and temperature value are predicted and validated. A good agreement is achieved when compared with experimental data. During phase change process, the numerical model is well exploited to investigate mass transfer in pipeline flow. The temperature drop along the pipe leads to the reduction of gas mass flow rate and the rise of liquid level, which results in further pressure drop. Latent heat is released during the vapor condensing process which slows down the temperature drop. Larger temperature drop results in bigger liquid holdup while larger pressure drop causes smaller liquid holdup. The value of velocity with phase change is smaller than that without phase change while the temperature with phase change is higher. The highest temperature locates in gas phase. But near pipe wall the temperature of liquid region is higher than gas region. Thus, the numerical model can be widely applied to predict the pipeline operating parameters and global fluid properties which are essential to the design of downstream equipment and the guarantee of flow assurance.

Advanced thermal management system based on paraffin wax (PW) is an effective method to alleviate the increasing energy consumption. In this work, a new encapsulated phase change material (EPCM) was prepared by in-situ dehydration and condensation reaction, which consists of silica shell derived from sodium silicate and PW core. The chemical structure, crystal structure and microstructure of EPCMs were characterized by FT-IR, XRD, OM, TEM and SEM, which proved that the PW was successfully encapsulated by silica shell. In addition, the DSC, TGA, and leakage testing demonstrated that EPCMs possessed depressed supercooling, good thermal stability and leak-proof performance. When the mass ratio of PW/SiO2 is 4:1, the encapsulation ratio and encapsulation efficiency can reach 74.51% and 75.58%, respectively, and the corresponding latent heat is 94.4 J/g (melting process) and −93.2 J/g (solidifying process). In addition, the heat storage/release rate, thermal regulation ability and thermal cycling ability indicated that the EPCM has good thermal management performance. Due to the low cost and availability of sodium silicate and PW, the encapsulation technology proposed in this work has great potential practical application feasibility in the field of thermal management, including packaging, clothing and architecture.

Using green and renewable bio-based resources to realize multifunctional polymers is highly desirable for developing the next generation of smart materials. Herein, a facile method was proposed to prepare the thermally induced dynamic phenol-carbamate cross-linked thermoset polyurethane with robust mechanical properties, self-healing, reprocessing, and shape memory. Owing to the introduction of tannic acid (TA) that could form phenol-carbamate networks with isocyanate groups, the prepared TA based polyurethane (TA-PU) showed enhanced thermal stability and improved mechanical properties. Meanwhile, high self-healing efficiency could also be obtained by adjusting and controlling the content of dynamic phenol-carbamate bonds incorporated in polyurethane main chains, which indicated a good balance between robust mechanical properties and high self-healing efficiency in our target polymer. Further reprocessing tests demonstrated that the networked TA-PU polymer could also be well recycled by hot-pressing and solution casting. In addition, benefiting from the reversible crystallizable switching segments, that capable of being triggered by heat energy (when temperature is higher than the melting temperature of the soft segment), and cross-linked net points, the prepared TA-PU film could quickly recover from temporary shape to permanent shape. This elaborate design provides a heuristic perspective for developing multifunctional smart polymers from bio-based resources.

In this work, the plasma was produced by irradiating a tungsten target with an 8 ns pulsed Nd:YAG (λ = 1064 nm) laser in a vacuum chamber under the pressure of 4 × 10− 4 Pa. The optical and particle emissions were systematically investigated using laser induced breakdown spectroscopy and time-of-flight mass spectroscopy respectively. The results showed that not only there were neutral and single ionized atoms in the laser induced plasma, but also quite a number of multi-charged ions were observed. The ion charge state was even up to 6 at the laser power density of ~ 11 GW/cm2. Time and space resolved optical spectroscopy was investigated by using a bundle of lined fibers. Meanwhile, the time-resolved mass spectrometric study of laser produced tungsten plasma was carried out. The variation in intensities of the different species with time showed that higher charged ions reached their peak intensities earlier. This demonstrated that the higher charged ions had higher velocities and the different charged ions were separated during the expansion process. The kinetic energy corresponding to the velocity of the ions was found to increase exponentially with ionic charge state which was related to the acceleration of the dynamic plasma sheath.

In this paper, the effect of magnetic field (1.1 T) on the atomic and ionic spectral emission of a laser produced lithium plasma at low pressure has been investigated. The experimental results indicate that magnetic field enhances the intensities of Li I spectral lines but reduces the Li II spectral lines intensities. In this study, two narrowband filters were placed before the ICCD camera to observe the evolution feature of Li II spectral line (548.39 nm, 2p3P2,1,0 → 2s3S1) and Li I spectral line (610.30 nm, 3d2P3/2, 5/2 → 2p2P1/2, 3/2), respectively. The plasma dynamic images show that with the magnetic field, the number density of luminous Li atoms is higher, while the number density of luminous Li ions is lower in comparison to the field-free case. The reduced Li II spectral intensities indicate that the quenching rate of Li ions in the excited state is greater than that without the magnetic field. The enhanced impact frequency of recombination indicates that magnetic field increases the recombination process of electron and Li ions. All of these observations strongly suggest that magnetic confinement increases the recombination process of the electrons with Li ions in the plasma, which results in the decrease in the intensity of Li II line. The results are useful for applying laser-induced breakdown spectroscopy (LIBS) to in-situ diagnose the processes of lithium wall conditioning in EAST tokamak.

This paper studies the finite-time H ∞ control problem for the nonlinear discrete Hamiltonian descriptor system (NDHDS). Firstly, based on a proper state-feedback controller, a strict dissipative system, which is equivalent to the NDHDS, is obtained. Then, two sufficient conditions are derived for finite-time boundedness and finite-time H ∞ boundedness of the strict dissipative system, and the obtained results are applied to finite-time H ∞ control problem for the NDHDS. Finally, a simulation example is given to illustrate the effectiveness of our results.

A seed-induced method was developed to synthesize aggregates of nano-sized ZSM-5 crystals by template-free MFI seeds and cetyltrimethyl ammonium bromide (CTAB). Various MFI zeolites after calcination, including: nano-sized silicate-1, nano-sized ZSM-5 aggregates and commercial bulk ZSM-5 crystals were used as seeds. A trace of CTAB could accelerate the crystallization and pure MFI structure was obtained in the presence of CTAB. More importantly, the aggregates of nano-sized ZSM-5 crystals were dramatically synthesized by transforming the bulk seeds into smaller sizes with NaOH treatment before crystallization. The resulting solid exhibited an excellent catalytic performance in the methanol to propylene reaction.

ZSM-11/5 composite zeolite was successfully synthesized through the addition of cetyltrimethylammonium bromide (CTAB) and seed, but in the absence of template. However, without the addition of CTAB, pure large hexagonal ZSM-5 crystals were formed in the presence of ZSM-11 as seed. The products were characterized by SEM, XRD, XRF, 27Al NMR, 27Si NMR, N2 physical adsorption and NH3-TPD. The SEM images imply that large ZSM-5 crystals gradually evolve from imperfect to perfect crystals, rather than forming small crystals first, and then gradually growing. The ZSM-11/5 composite zeolite exhibited hierarchical characteristics with higher specific surface areas, higher external surface areas, higher mesopore volumes and more acid sites than the sample synthesized by the conventional method with tetrabutylammonium as template. The ZSM-11/5 composite zeolite also exhibited excellent catalytic properties in the reaction of methanol to hydrocarbons.

In this paper, laser-induced breakdown spectroscopy (LIBS) under magnetic field condition has been studied in laboratory and EAST tokamak. The experimental results reveal that in helium ambient gas, the magnetic field significantly enhances the LIBS signal intensity (∼3 times). The effect of time delay and laser fluence on the intensity of LIBS has been investigated for optimizing the signal to background ratio (S/B). The developed LIBS approach has been applied to monitor the cleaning performance of the first wall in the fusion device of EAST using the ion cyclotron range of frequency (ICRF). The experimental results demonstrate that the cleaning performance for Li/D co-deposition layer is effective under helium ambient gas. The removing rate of Li on the surface of W tile is faster than that on Mo tile in He-ICRF cleaning and the D/(D + H) ratio on Mo tile is higher by ∼1.2 times than that on W tile. This work would indicate the feasibility of using LIBS to monitor the wall cleaning processes in EAST tokamak.

In this article, we propose a kind of numerical methods based on the Pade approximations, for two kinds of stochastic Hamiltonian systems. For the general linear stochastic Hamiltonian systems, it is shown that the applied Pade approximations P ( k , k ) produce numerical solutions that are symplectic, and the proposed numerical schemes based on P ( r , s ) are of root-mean-square convergence order r + s 2 . For a special kind of linear stochastic Hamiltonian systems with additive noises, the numerical methods using two kinds of Pade approximations, P ( r ź , s ź ) and P ( r ź , 1 ) , possess root-mean-square convergence order r ź + 2 when r ź + s ź = r ź + 3 , and are symplectic if r ź = s ź . These generalize the Pade approximation approaches for symplectic integration of linear Hamiltonian systems to the stochastic context.

Realizing environment-friendly and thermal-driven self-healing polymers with robust mechanical properties is an important challenge for the development of next-generation smart materials. Herein, by combining dynamic phenol-carbamate bonds and Fe3+-catechol coordination bonds in polymer chains, novel hyperbranched waterborne polyurethanes (FTWPU) with desirable thermal-driven self-healing properties were prepared through two steps, i.e., introducing tannic acid to prepare tannic acid based waterborne polyurethane (TWPU) bearing phenol-carbamate bonds firstly, and subsequently further incorporating Fe3+ ions to prepare FTWPU in possession of Fe3+-catechol moieties. The results exhibited that TWPU possessed good emulsion stability with differing tannic acid content, and improved thermal and mechanical properties, owing to the presence of cross-linking between polyurethane chains, and FTWPU still possessed outstanding storage stability, as well as much higher mechanical properties (tensile strength of 18.4 ± 0.4 MPa, elongation at break of 533.5 ± 5.2 %). Meanwhile, FTWPU presented desirable self-healing ability (i.e., healing efficiencies of tensile strength and elongation at break were 87.5 % and 91.9 %, respectively) after healing under 120 °C for 1.5 h and 85 °C for 30 min, demonstrating a satisfactory balance between good self-healing ability and high mechanical properties. Importantly, reversible phenol-carbamate bonds and metal coordination bonds are predominant factors during the healing process of FTWPU films, as well as high mobility of soft segments and hydrogen bonding effect play a significant role to achieve ultimate healing ability. We can envision that the promising design idea, based on synergistic effect between phenol-carbamate bonds and Fe3+-catechol coordination bonds, could provide inspiration for preparing self-healing polymers with superior mechanical properties.

The effect of ageing regimes at temperatures in a range from 400 °C to 520 °C and time for up to 120 h on the spinodal decomposition of austenite in an as-quenched Mn–13Cu alloy is investigated using small-angle neutron scattering and in situ neutron diffraction. The as-quenched from 850 °C alloy has a 100% antiferromagnetic martensitic structure that can be described as a face-centered tetragonal (f.c.t.) lattice at room temperature (RT). In the early stage of the ageing process (for 8 h at 400–480 °C or for the first 16 h at 440 °C), the decomposition of the high-temperature face-centered cubic (f.c.c.) phase into an Mn-rich f.c.c. matrix and Cu-rich clusters takes place. Higher ageing temperature or longer ageing time leads to the formation of α-Mn inclusions with a body-centered cubic (b.c.c.) structure, retained after cooling to RT. Martensitic transition temperatures strongly depend on the ageing temperature and time, i.e., on the degree of chemical decomposition in austenite. The linear relationship between phase transition temperatures and Mn content in the matrix is quantitatively established. The thermal hysteresis between a direct and reverse phase transition does not change with ageing treatment. According to the in situ neutron diffraction results, structural and magnetic transitions occur at the same temperature during heating and cooling.

A non-equilibrium mechanism for nanosecond laser ablation is suggested herein, and its predictions are compared to the results of W experiments performed under vacuum conditions. A mechanism of particle formation is explained via this model, with partial sublimation of the superheated irradiated zone of the target considered to be the mechanism of laser ablation. In this study, a mixture of vapor and particles was explosively generated and subsequently prevented the rest of a laser pulse from reaching its intended target. This mechanism was found to play an essential role in the ablation of W under vacuum conditions, and it provides a theoretical justification for particle formation. Moreover, special considerations were taken into account for the expansion of plasma into a vacuum. The model was evaluated by measuring the mass of ablated particles using a quartz crystal deposition monitor and time-resolved optical emission spectroscopy. The results of this model were found to be in good agreement with experimental values.

In this paper, we study the eigenvalue problems of a class of nonlinear fractional q -difference equations with generalized p -Laplacian involving the Riemann–Liouville fractional derivative. By means of fixed point theorem in cones, some results of positive solutions are obtained.

Suspended sediment dynamics were investigated in the Loushui River basin, a secondary tributary of the Yangtze River in southern China. The variations of suspended sediment transport were analyzed at different time scales (among different years, monthly and seasonal, and within-flood event) based on 25-year hydrological data from the outlet hydrometric station, and explained by the contribution of flood events, precipitation and human activities. Four stages were classified by the non-parametric statistical method of Pettitt change-point test and Cumulative anomaly test. At the annual scale, the relationship between suspended sediment concentration (SSC) and water discharge (Q) varied at four stages. The suspended sediment load (SSL) showed parabolic relationship with annual precipitation and significantly influenced by floods (contribution averaged at 78% before 1985; at 55% after 2007). SSL drastically decreased after 2007, mainly induced by the construction of the Jiangya reservoir. Sediment ‘store-release’ phenomenon was used to explain the seasonal variations of suspended sediment load. Monthly SSC–Q hysteresis loops indicated that the sediment storage seasons swung between winter/spring and late autumn at different stages. At the within-flood scale, three types of SSC–Q hysteresis loops were observed for the maximum flood events, including clockwise pattern (44%), counter-clockwise pattern (24%) and figure-eight pattern (32%). The variations of SSC–Q hysteresis patterns at four stages implicated the changing suspended sediment source materials with time. During the years 1966–1978, the suspended sediment mainly came from channels for the maximum flood events, while, materials from the upper reaches or slopes dominated the later period 1979–1985 and 2007–2011.

Flow velocity is one of the most significant hydraulic parameters directly connected to sediment transport-deposition processes. Four soils were collected from north to south of the Loess Plateau, namely Sandy Loess (SL), Loessial Soil (LS), Heilu Soil (HS) and Anthrosol Soil (AS), to examine the impacts of soil property on mean flow velocity in both interrill and rill flows under different simulated rainfall experiments. The mean velocity of interrill flow (MVIF) followed the order of LS > HS ≈ AS > SL at 90 mm h−1 rainfall intensity and LS > HS > AS > SL at 120 mm h−1 rainfall intensity. The mean velocity of rill flow (MVRF) decreased as LS ≈ HS > AS at 90 mm h−1 and LS ≈ HS > AS > SL at 120 mm h−1. The order of MVIF and MVRF on four soil slopes is determined by the relations of runoff discharge, Darcy-Weisbach friction factor in interrill area (fI) and rills (fR), which are closely related to soil properties. Soil properties also changed the effects of rainfall intensity on flow velocities in different erosion stages, resulting in the increasing trend of MVIF on SL, HS and AS slopes and the decreasing trend of MVIF on LS slope with the increase of rainfall intensity. Moreover, soil properties may change the variations of MVIF and MVRF with the increase of slope gradient, by altering the relations of sealing progress and slope effect. The slope effect determined the increasing trend of MVIF with the increase of slope gradients. However, the sealing progress may offset the slope effect and cause the decrease of MVIF on the critical slopes, and the critical slope decreased from the north (20° and 25°) to the south (15°). The equal roles of rill bed roughness and slope effect caused the unchanged of MVRF on LS and HS slopes, while rill bed roughness dominated the fluctuations of MVRF on SL and AS slopes.

Sediment deposition is an important part of the erosion process. Slope and soil type affect the spatial distribution of erosion–deposition; however, little is known about where erosion and deposition occur specifically and how they interact with influencing factors. To address this issue, four rainfall simulation experiments were conducted in a 1 m × 5 m plot with varying slopes (i.e., 5°, 10°, 15°, and 20°) and simulated rainfall for 1 h at a rate of 60 mm h−1. For the two soils, the runoff rate and sediment concentration were correlated with a similar temporal pattern. Runoff increased gradually and ultimately approached a steady state, and the sediment concentration decreased gradually and ultimately approached a steady state, which indicated that the erosion processes of the two soils were controlled by the detachment-limited condition. The sediment concentration and erosion rate were positively correlated with slope. However, the onset of runoff was delayed for AS soil, which also had a relatively high sediment concentration. The distribution range and area of deposition for the two soils were negatively correlated with the slope gradient, and the main deposition area occurred at the bottom of the plots. In contrast, the SD soil was more susceptible to deposition, and the deposition thickness was mainly concentrated within a 0–4 mm depth; this concentration was not observed for AS soil because of its high erosion intensity. Overall, this similarity also existed in the spatial variations of silt and fine sand contents in the soil surface. The silt and fine sand-sized particles were the primary eroded particle sizes; however, selective mechanisms of these two particle sizes were obviously different in the two soils. The results indicated that the erosion–deposition characteristics and the main eroded materials differed with varying erosion intensities and soil types. These findings are essential for a more comprehensive understanding of soil erosion mechanisms under conditions without rill formation.