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In recent years, dysprosium macrocycle single-molecule magnets (SMMs) have received increasing attention due to their excellent air/thermal stability, strong magnetic anisotropy, and rigid molecular skeleton. However, they usually display fast zero-field quantum tunneling of the magnetization (QTM) rate, severely hindering their data storage applications. Herein, we report the design, synthesis, and characterization of an air-stable monodecker didysprosium macrocycle integrating strong single-ion anisotropy, near-perfect local crystal field (CF) symmetry, and efficient exchange bias. These indispensable features enable clear-cut elucidation of the crucial role of very weak antiferromagnetic coupling on magnetization dynamics, creating a prominent SMM with a large effective energy barrier (Ueff) of 670 cm–1, open hysteresis loops at zero field up to 14.9 K, and a record relaxation time of QTM (τQTM), 24281 s, for all known nonradical-bridged lanthanide SMMs.

Most industrial processes feature high nonlinearity, non-Gaussianity, and time correlation. Models based on overcomplete broad learning system (OBLS) have been successfully applied in the fault monitoring realm, which may relatively deal with the nonlinear and non-Gaussian characteristics. However, these models barely take time correlation into full consideration, hindering the further improvement of the monitoring accuracy of the network. Therefore, an effective dynamic overcomplete broad learning system (DOBLS) based on matrix extension is proposed, which extends the raw data in the batch process with the idea of “time lag” in this article. Subsequently, the OBLS monitoring network is employed to continue the analysis of the extended dynamic input data. Finally, a monitoring model is established to tackle the coexistence of nonlinearity, non-Gaussianity, and time correlation in process data. To illustrate the superiority and feasibility, the proposed model is conducted on the penicillin fermentation simulation platform, the experimental result of which illustrates that the model can extract the feature of process data more comprehensively and be self-updated more efficiently. With shorter training time and higher monitoring accuracy, the proposed model can witness an improvement of average monitoring accuracy by 3.69% and 1.26% in 26 process fault types compared to the state-of-the-art fault monitoring methods BLS and OBLS, respectively.

The impact of acupuncture on knee function and pain intensity following knee replacement remains controversial. Therefore, we categorized the postsurgery recovery period into 3 phases: short-term (≤2 weeks), intermediate-term (2 weeks–3 months), and long-term (>3 months), and then assessed the effectiveness of acupuncture in improving function and alleviating pain at different stages following knee replacement. This meta-analysis included randomized controlled trials that compared acupuncture intervention with either no treatment or a sham group after knee replacement. Six databases were searched from inception to December 31, 2023, including PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and 2 Chinese databases (Chinese National Knowledge Infrastructure and WanFang Data). A total of 23 studies comprising 1,464 participants were included. Significant improvement of active range of motion was observed on day 7 and week 2 after operation. Lower pain intensity at rest was noted in patients receiving acupuncture in short-term periods after operation (12 hours, day 1, day 2, day 5, and week 2). A reduction in pain intensity during movement with acupuncture was observed on postoperative day 1 and day 7. Auricular acupuncture did not show not significant effectiveness in improving range of motion and pain intensity. For conventional acupuncture, the combination of distal and local point selection was found to be the most effective. Early application of acupuncture, in conjunction with physical therapy, starting before postoperative day 1 or day 2, was recommended. Further high-quality researches are warranted to validate the findings in this meta-analysis.

Cadmium (Cd) plays a key role in the occurrence of myocardial infarction (MI). We aimed to explore the association between blood Cd levels and all-cause mortality of MI on the basis of the National Health and Nutrition Examination Survey databases. This study included 800 adults with MI to obtain blood Cd concentrations and their follow-up information. The association between Cd concentrations and mortality was analyzed using Cox regression, restricted cubic spline (RCS) models, mediation analysis, receiver operating characteristic curve, and Kaplan–Meier curves. All the patients were divided into 4 groups according to the quartiles of blood Cd levels (Q1, Q2, Q3, and Q4). Cox regression analysis with adjustment for covariates indicated that Cd was the promoting factor of mortality, and patients with higher Cd had a higher death risk. The RCS model indicated an “inverted checkmark” shaped correlation between Cd levels and mortality, and a turning point of 1.06 μg/L was found. A significant positive correlation was observed on the left of the turning point. Grouped patients by turning point into 2 groups, Kaplan–Meier analysis showed that the low-concentration group had a lower death risk than the high-concentration group. Subgroup analysis revealed that the prognostic effect of Cd was more pronounced in patients with former smoking history, and receiver operating characteristic curve showed that blood Cd had a better-predicting function in patients with MI. Blood Cd levels were significantly related to all-cause mortality in patients with MI, especially in patients with Cd < 1.06 μg/L.

Design and synthesis of air-stable and easily tailored high-performance single-molecule magnets (SMMs) are of great significance toward the implementation of SMMs in molecular-based magneto-electronic devices. Here, by introducing electron-withdrawing fluorinated substituents on equatorial ligand, two chiral Dy(III) macrocyclic complexes, RRRR-Dy-D6hF12(1) and SSSS-Dy-D6hF12(2), with a record anisotropy barrier exceeding 1800 K and the longest relaxation time approaching 2500 s at 2.0 K for all known air-stable SMMs, were obtained. The nearly perfect axiality of the ground Kramers doublet (KD) enables the open hysteresis loops up to 20 K in the magnetically diluted sample. It is notable that they are structurally rigid with high thermal stability and the apical ligand can be tailored to carry proper surface-binding groups. This finding not only improves the magnetic properties for air-stable SMMs but also provides a new avenue for deposition of SMMs on surfaces.

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1532-5415.2008.01996.x Byline: Xu Hui Ying (*), Ajeet M. Wagle (*[dagger][double dagger]), Lawrence Tan (*), Srinivasan Sanjay ([dagger][double dagger]), Smita R. Hedge ([dagger][double dagger]), Yip Chee Chew ([dagger][double dagger]s.[parallel]), Philip Yap (*) Author Affiliation: (*)Department of Geriatric Medicine, Alexandra Hospital, Singapore ([dagger])Department of Ophthalmology and Visual Sciences, Alexandra Hospital, Singapore ([double dagger])The Eye Clinic, Jurong Medical Centre, Singapore (s.)Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore ([parallel])Department of Ophthalmology, Tan Tock Seng Hospital, Singapore

The present study aims to investigate the effects of dietary Chinese herbs mixture (CHM) including Artemisia capillaris, Gardenia jasminoides, Scutellaria baicalensis, Reynoutria japonicaand Uncaria rhynchophyllaon the growth performance, anti-oxidative and immune responses, and intestine and liver histology of juvenile large yellow croaker Larimichthys crocea(initial body weight: 17.03 ± 0.03 g), which were fed graded levels of CHM (0 (control group), 250, 500 and 750 mg/kg, respectively) for 60 days. The results indicated that supplementing 250 and 500 mg/kg CHM in diet significantly increased the weight gain rate and decreased the feed conversion ratio of juvenile large yellow croaker (P< 0.05). The activities of lipase, chymotrypsin, γ-glutamyl transferase and Na+, K+-ATPase were significantly increased in CHM250 and/or CHM500 groups (P< 0.05). Besides, the levels of total anti-oxidative capacity, immunoglobulin M, complement 3 and complement 4 were significantly increased in the CHM250 and/or CHM500 groups (P< 0.05). The expressions of anti-oxidation gene (nuclear factor erythroid 2-related factor 2, nrf2), anti-inflammatory cytokines (interleukin-10, il-10and transforming growth factor-β, tgf-β) and anti-apoptotic gene (B-cell lymphoma-2, bcl-2) in liver were significantly up-regulated, while the malondialdehyde content and the expressions of kelch like ECH associated protein 1 (keap1) and nuclear factor κB p65 (nf-κb p65) were significantly down-regulated after supplementing 250 and/or 500 mg/kg CHM in diet (P< 0.05). The histological analysis of liver and intestine showed the better morphology in CHM250 and CHM500 groups than the control group. In conclusion, above results indicated that dietary CHM (250 – 500 mg/kg) significantly improved the growth performance, anti-oxidative capacity, immunity and histology of liver and intestine of juvenile large yellow croaker.

Introduction: Wutou decoction has been wildly applied for the treatment of RA in China for several thousand years. Methods: This study aims to develop a highly sensitive and specific ultra performance liquid chromatography coupled with tandem mass spectrometry and electrospray ionization (UPLC-ESI-MS/MS) method to explore the pharmacokinetic properties of three representative bioactive alkaloids after intragastric administration of Wutou decoction in rats. Chromatographic separation was performed on a C18 column under the Multiple Reaction Monitoring (MRM) in the positive electrospray ionization (ESI) mode. The pharmacokinetic parameters were evaluated by software DAS 3. 0. Results: The validation of the method was achieved in accordance with the FDA guidelines. The results of pharmacokinetic study showed that the in vivo concentrations of benzoylmesaconine and benzoylhypaconine were significantly higher than benzoylaconine. Our PK results showed that these three compounds were quickly absorbed after the administration of Wutou decoction, and Tmax ranged from 30 min to 45 min. Conclusion: The results of pharmacokinetic study showed that the in vivo concentrations of benzoylmesaconine and benzoylhypaconine were significantly higher than benzoylaconine. There were also similar pharmacokinetic behaviors observed among BAC, BHA, and BMA after oral administration of WTD.

'Akizuki' (Pyrus pyrifolia Nakai) is a dominant Asian pear cultivar with gradually increasing cultivation area in Shandong province. However, this cultivar is found susceptible to cork spot disorder in recent years. In this study, we explored the physiological-biochemical mechanism of cork spot disorder in pear fruit, and investigated the effectiveness of spraying calcium (Ca), boron (B) solution or prohexadione calcium (P-Ca) on cork spot incidence. Cork spotted fruit had the characteristics of significantly larger fruit size with shorter fruit pedicels. Compared with normal fruit, cork spotted fruit had lower content of total soluble solids, soluble and reducing sugar, and vitamin C. In addition, cork spotted fruit accumulated much higher levels of N and Mg, and lower levels of K and P. However, Ca deficiency was not observed in cork spotted fruit, on the contrary, we determined high concentrations of Ca and free Ca2+ in disordered fruit. At the same time, the ratios of K/Ca, Mg/Ca, and (K+Mg)/Ca were significantly lower in cork spotted fruit as compared with normal fruit. Among all treatments, spraying with 3500 times dilution of P-Ca at 15-day intervals from 30 to 90 days after full bloom showed promise for reducing cork spot incidence in 'Akizuki' pear without affecting fruit quality attributes. This research herein reveals the physiological-biochemical characteristic of cork spot disorder, and implicates P-Ca as a potential tool to reduce cork spot incidence in Asian pear cultivar Akizuki. [ABSTRACT FROM AUTHOR]

We report two pairs of enantiomers of Co(II)- and Zn(II)-based metallacycles constructed by coordination-driven self-assembly between homochiral 1,1′-bi-2-naphthol-derived ligands featuring two kinds of coordination pockets and transition-metal ions. Remarkably, they exhibit calix[4]arene-like topological structures and fascinating chiral cavities, having potential in enantioselective recognition.

Duchenne muscular dystrophy (DMD) is a disabling and life-threatening, X-linked recessive disorder caused by mutations in dystrophin. Natural history studies can inform the disease characteristics of DMD, and data from these studies can be used to plan and design clinical trials and as external controls for long-term studies. We report 12-month results from the largest natural history study of individuals with DMD in China receiving standard of care treatment.

Aim:We have reported novel anticancer bioactive peptides (ACBPs) that show tumor-suppressive activities in human gastric cancer, leukemia, nasopharyngeal cancer, and gallbladder cancer. In this study, we investigated the effects of ACBPs on human colorectal cancer and the underlying mechanisms.Methods:Cell growth and apoptosis of human colorectal tumor cell line HCT116 were measured using cell proliferation assay and flow cytometry, respectively. The expression levels of PARP, p53 and Mcl1A were assessed with Western blotting and immunohistochemistry. For evaluation of the in vivo antitumor activity of ACBPs, HCT116 xenograft nude mice were treated with ACBPs (35 μg/mL, ip) for 10 days.Results:Treatment of HCT116 cells with ACBPs (35 μg/mL) for 4–6 days significantly inhibited the cell growth. Furthermore, treatment of HCT116 cells with ACBPs (35 μg/mL) for 6–12 h significantly enhanced UV-induced apoptosis, increased the expression of PARP and p53, and decreased the expression of Mcl-1. Administration of ACBPs did not change the body weight of HCT116 xenograft nude mice, but decreased the tumor growth by approximately 43%, and increased the expression of PARP and p53, and decreased the expression of Mcl-1 in xenograft mouse tumor tissues.Conclusion:Administration of ACBPs inhibits human colorectal tumor cell growth and induces apoptosis in vitro and in vivo through modulating the PARP-p53-Mcl-1 signaling pathway.

To evaluate the estrogenic efficacy of Renshen (Radix Ginseng) (GS) on reproductive target tissues in immature mice.

Soil phosphomonoesterase plays a critical role in controlling phosphorus (P) cycling for crop nutrition, especially in P-deficient soils. A 6-year field experiment was conducted to evaluate soil phosphomonoesterase activities, kinetics and thermodynamics during rice growth stages after consistent swine manure application, to understand the impacts of swine manure amendment rates on soil chemical and enzymatic properties, and to investigate the correlations between soil enzymatic and chemical variables. The experiment was set out in a randomized complete block design with three replicates and five treatments including three swine manure rates (26, 39, and 52 kg P ha−1, representing low, middle, and high application rates, respectively) and two controls (no-fertilizer and superphosphate at 26 kg P ha−1). The results indicated that the grain yield and soil chemical properties were significantly improved with the application of P-based swine manure from 0 to 39 kg P ha−1; however, the differences between the 39 (M39) and 52 kg P ha−1treatments (M52) were not significant. The enzymatic property analysis indicated that acid phosphomonoesterase was the predominant phosphomonoesterase in the tested soil. The M39and M52treatments had relatively high initial velocity (V0), maximal velocity (Vmax), and activation grade (lgNa) but low Michaelis constant (Km), temperature coefficient (Q10), activation energy (Ea), and activation enthalpy (ΔH), implying that the M39and M52treatments could stimulate the enzyme-catalyzed reactions more easily than all other treatments. The correlation analysis showed that the distribution of soil phosphomonoesterase activities mainly followed the distributions of total C and total N. Based on these results, 39 kg P ha−1could be recommended as the most appropriate rate of swine manure amendment.

AbstractThe changes in a selection of extreme climate indices (maximum of daily maximum temperature (TXx), minimum of daily minimum temperature (TNn), annual total precipitation when the daily precipitation exceeds the 95th percentile of wet-day precipitation (very wet days, R95p), and the maximum number of consecutive days with less than 1 mm of precipitation (consecutive dry days, CDD)) were projected using multi-model results from phase 5 of the Coupled Model Intercomparison Project in the early, middle, and latter parts of the 21st century under different Representative Concentration Pathway (RCP) emissions scenarios. The results suggest that TXx and TNn will increase in the future and, moreover, the increases of TNn under all RCPs are larger than those of TXx. R95p is projected to increase and CDD to decrease significantly. The changes in TXx, TNn, R95p, and CDD in eight sub-regions of China are different in the three periods of the 21st century, and the ranges of change for the four indices under the higher emissions scenario are projected to be larger than those under the lower emissions scenario. The multi-model simulations show remarkable consistency in their projection of the extreme temperature indices, but poor consistency with respect to the extreme precipitation indices. More substantial inconsistency is found in those regions where high and low temperatures are likely to happen for TXx and TNn, respectively. For extreme precipitation events (R95p), greater uncertainty appears in most of the southern regions, while for drought events (CDD) it appears in the basins of Xinjiang. The uncertainty in the future changes of the extreme climate indices increases with the increasing severity of the emissions scenario.

AbstractA regional climate model (RegCM4) is employed to investigate the impacts of land use/cover change (LUCC) on the climate over the eastern part of Northwest China (ENW) in the periods of 2001 and 2011. The results indicated that the LUCC in ENW, which was characterized by desert retreat, reforestation, and farmland expansion, led to significant local changes in surface air temperature (within ∼0.3C) and slight regional changes in precipitation (within ∼15%) in summer. In the desert retreat area, the net absorbed shortwave radiation had a greater influence than evaporative cooling, leading to increases in the daily mean and maximum temperature. Besides, the daily mean and maximum temperatures increased in the reforestation area but decreased in the farmland expansion area. As surface albedo showed no significant change in these regions, the temperature increase in the reforestation area can be attributed to a decrease in evaporation, while the opposite effect appears to have been the case in the farmland expansion area.

AbstractBased on GISS-E2-R model simulations, the changes in PM2.5and ozone concentrations during 2016–35 are analyzed over the Jing-Jin-Ji region under different future emissions scenarios: 2.6, 4.5, 6.0, 8.5 Representative Concentration Pathways scenarios (RCP2.6, RCP4.5, RCP6.0, and RCP8.5), compared to the baseline periods of 1851–70 (pre-industrial) and 1986–2005 (present day). The results show that PM2.5increases under all emissions scenarios, with the maximum value occurring in the southeastern part of the region under most scenarios. As for ozone, its concentration is projected to increase during 2016–35 under all emissions scenarios, compared to the baseline periods. The temporal evolutions of PM2.5and ozone show PM2.5reaching a peak during 2020–40, while ozone will likely increase steadily in the future.

Through the software defect prediction can effectively guide the rational distribution of software system development resources, so as to improve the quality of software and software reliability. In order to fully utilize the existing historical data to guide the software development of existing software system development, this paper based on an improved classification and regression tree (Classification and Regression, CART) algorithm software defect prediction models. The paper first principal component analysis of the data predicted correlation dimension (Principle Component Analysis, PCA) between data and reduce the data, and configured according to the theory and optimized CART decision tree algorithm, existing software defect prediction system, and with traditional defect prediction method, the experimental results show that the proposed prediction model has higher prediction accuracy and stability.

According to the signal-to-noise ratio (SNR) loss of average algorithms in direct P-code acquisition method, this paper analyzes the SNR performance of the overlap average algorithm quantitatively, and derives the relationship of SNR loss with overlap shift value and initial average phase difference in the overlap average algorithm. On this basis, the bidirectional overlap average algorithm based on optimal correlation SNR is proposed. The algorithm maintains SNR consistent in the entire initial average phase difference space, and has a better SNR performance than the overlap average algorithm. The effectiveness of the algorithm is verified by both theoretical analysis and simulation results. The SNR performance of the bidirectional overlap average algorithm is 5 dB better than that of the direct average algorithm, and 2 dB better than that of the overlap average algorithm, which provides the support for direct P-code acquisition in low SNR. [ABSTRACT FROM AUTHOR]

The target of this paper is to introduce the improvement of the technique of image retrieval. At first, it comes up with the concept of image retrieval and shows the importance of this technique. As the techniques of multimedia and Internet are developing rapidly, the resources of images that users obtain are also extended. And then this paper gives the problem about the image retrieval, namely the information of images are disordering. As the result, it is significant to do the effective organization, management and retrieval based on the increasingly extensive image information storage. After that, this paper presents the concept of TBIR and CBIR and gives the definitions of them. It proposes an issue that CBIR is the improvement of TBIR. Based on CBIR, there are also some disadvantages that need to be improved. In terms of the main point of CBIR, the paper raises that the annotation is one of the most difficult techniques that need to be promoted. Then it describes some algorithms about the technique of automatic image annotation. After these algorithms, the paper shows the challenges and developing direction of the technique of image retrieval. At last, it presented the conclusion to emphasize the main points of this paper.

The Nongruri gold deposit is located in Mozhugongka, Tibet.There are two occurrence states of gold in Nongruri deposit, native gold and lattice gold. Fine grained native gold is hosted in clay minerals, and lattice gold just occupies little part. Gold particle size ranges from less than 0.001mm to 0.034mm, mainly in > 0.02mm, about 52.13wt% of total mount. According to the composition of mineral, occurrence state of gold and particle size measurement results of gold and gold-bearing mineral, it is a kind of fine-grained uneven refractory ore, and the recommended grind size should be smaller than-200 mesh.

Based on the simulations of 22 CMIP5 models in combination with socio-economic data and terrain elevation data, the spatial distribution of risk levels of flood disaster and the vulnerability to flood hazards in China are projected under the RCP8.5 for the near term period (2016–2035), medium term period (2046–2065) and long term period (2080–2099), respectively. The results show that regions with high flood hazard levels are mainly located in Southeast China, while the vulnerability to flood hazards is high in eastern China. Under the RCP8.5 greenhouse gas emissions scenario, future high flood risk levels will mainly appear in the eastern part of Sichuan, in major part of East China, and in the provinces of Hebei, Beijing, and Tianjin. The major cities in Northeast China, some areas in Shaanxi and Shanxi, as well as the coastal areas in southeastern China will also encounter high flood risks. Compared with the baseline period, the regional flood risk levels will increase towards the end of the 21st century, although the occurrences of floods change little. Due to the coarse resolution of the climate models and the indistinct methodology for determining the weight coefficients, large uncertainty still exists in the projection of flood risks.

According to the requirements of the high-sensitivity acquisition of Direct Sequence Spread Spectrum (DSSS) signals under ultrahigh dynamic environments in space communications, a three-dimensional joint search of the phase of Pseudo-Noise-code (PN-code), Doppler frequency and its rate-of-change is presented to achieve high sensitivity in sensing high-frequency dynamics. By eliminating the correlation peak loss caused by ultrahigh Doppler frequency and its rate-of-change offset, the proposed method improves the acquisition sensitivity by increasing the non-coherent accumulation time. The validity of the algorithm is proved by theoretical analysis and simulation results. It is shown that signals with a carrier-to-noise ratio as low as 39 dBHz can be captured with high performance when the Doppler frequency is up to ±1 MHz and its rate-of-change is up to ±200 kHz/s.

The effect of flow coefficients, working pressures, nozzle layout and aircraft angle on extinguishing aircraft cabin fire by water mist were studied by experiment. The results show that the fire suppression effectiveness is increased with the increase of flow coefficient and working pressure; the diamond-shaped layout in sprinkler is better than square layout,and the aircraft angle of 30° is better than of 10°or 20°.

The objective of this work is to investigate the diesel analog pool fire with water mist .For this purpose, a series of water mist fire suppression experiment are carried out by changing the nozzle operating pressure, the source of fire power, opening and closing the exhaust fan to analyze the inhibitory effect of water mist to oil pool fire in the enclosed compartment of 5.0m × 5.0m × 3.0m. The results shows that extinguishing efficiency first increases and then decreases when the nozzle operating pressure increases from 8MPa to 12MPa, reaching the highest efficiency at 10MPa; increasing the power of the source of fire, the burning speed increases and the water mist fire extinguishing efficiency decreases; fresh oxygen coming in when smoke exhaust fan is turned on and water mist fire suppression efficiency decreases. Using FDS to simulate the water mist extinguishing oil pool fire, the predict temperature field and extinguishing time are basically consistent with the experimental results. In the actual applications of water mist fire suppression systems engineering, we can use the FDS field simulation methods to predict the characteristic parameters variation of the fire fighting fire temperature and component concentration, which is significant to the fire extinguishing system optimized design.

In this study, a coupled coal and power management model is developed based on an inexact fuzzy-queue programming method. The model is applied to a case study of coupled coal and power management system. The results indicate that the developed model can afford reasonable measures for solving coal-blending and coal-resources-allocation problems in coupled coal and power management system. It is useful for (a) standardizing coal supply, (b) improving efficiencies of the boilers, and (c) reducing emissions of air pollutants for meeting local air-quality targets. Potential risks associated with coal shortages and instability due to property variations from multiple sources can also be highly lowered through diversifying coal sources. Moreover, it can handle queue problems and multiple uncertainties exist in coupled coal and power management activities. Thus, it can help decision makers obtain optimal coal-blending schemes and coal-allocation patterns.

This paper presents an experimental study of fire suppression effectiveness with water mist containing FeCl2 additives.The investigation focuses on suppression effectiveness under various FeCl2 additives concentrations,working pressures and nozzle different height above the fire source . The experimental results show that: there is a significant impact on fire suppression effectiveness when adding FeCl2 to water mist. There is an optimum additive concentration of extinguishing fire, corresponding to the shortest extinguishing time, the least amount of water, the highest efficiency of extinguishing fire. The nozzle working pressures and nozzle position have effect on the performance of the water mist extinguishing: the greater the pressure is, the shorter water mist fire extinguishing time is. Under the same experimental conditions, the closer the water mist nozzles are to the oil pan, the shorter extinguishing time is.

This paper gives a rough review of the intelligent control strategies used in BLDC (Brushless Direct Current) motor controller. The development history of BLDC motor is introduced firstly. The parameter setting problems in a traditional PID control method are analyzed secondly. Then, an intensive introduction on the intelligent control strategies those are used in the PID control system is presented. Finally, the development trend of the intelligent control strategies in the BLDC motor control is discussed.

By assuming constant winter wheat varieties and agricultural practices in China, the influence of climate change on winter wheat is simulated using the corrected future climate projections under SRES A2 and A1B scenarios from 2012 to 2100, respectively. The results indicate that the growth of winter wheat would be strongly influenced by climate change in future. The average flowering and maturity dates of winter wheat would advance by 26 and 27 days under scenario A2, and by 23 and 24 days respectively under scenario A1B from 2012 to 2100. The simulated potential productivity of winter wheat shows a decrease of 14.3% and 12.5% for scenarios A2 and A1B respectively without the fertilization effect of CO2, while an increase of 1.3% and 0.6% with the fertilization effect of CO2. Additionally, for northern China, the simulated potential productivity would markedly decrease under both scenarios, independent with the fertilization effect of CO2, which indicates that the current planted winter wheat would be more vulnerable than that in southern China. The most likely reason is the current winter wheat varieties in northern China are winter varieties or strong winter varieties, which need some days of low temperature for dormancy. While in southern China, the winter wheat is spring or half winter varieties and can grow slowly during winter, thus, they would be affected slightly when winter temperature increases. The results of this study may have important implications for adaptation measures.

AbstractClimate changes in 21st century China are described based on the projections of 11 climate models under Representative Concentration Pathway (RCP) scenarios. The results show that warming is expected in all regions of China under the RCP scenarios, with the northern regions showing greater warming than the southern regions. The warming tendency from 2011 to 2100 is 0.06°C/10 a for RCP2.6, 0.24°C/10 a for RCP4.5, and 0.63°C/10 a for RCP8.5. The projected time series of annual temperature have similar variation tendencies as the new greenhouse gas (GHG) emission scenario pathways, and the warming under the lower emission scenarios is less than under the higher emission scenarios. The regional averaged precipitation will increase, and the increasing precipitation in the northern regions is significant and greater than in the southern regions in China. It is noted that precipitation will tend to decrease in the southern parts of China during the period of 2011–2040, especially under RCP8.5. Compared with the changes over the globe and some previous projections, the increased warming and precipitation over China is more remarkable under the higher emission scenarios. The uncertainties in the projection are unavoidable, and further analyses are necessary to develop a better understanding of the future changes over the region.

AbstractBased on 18 global climate models' simulations of the 20th century climate, a set of experiments within phase five of the Coupled Model Inter-comparison Project (CMIP5), the performances of simulating the pre-sent climate over China are assessed. Compared with observations, models can capture the dominant features of the geographic distributions of temperature and precipitation during 1961–2005. For the temporal changes of temperature, models appear to have a good performance on reproducing the warming tendency but show limited skills for precipitation. For the regional mean temperature and precipitation over the whole of China, most models underestimate the actual temperature and overestimate precipitation. Concerning the standard deviations of simulations by the 18 models, they are larger for temperature in the western part of China, while the standard deviations are larger for precipitation in the South.

Preparation and characterization of well‐organized zeolitic nanocrystal aggregates with an interconnected hierarchically micro–meso–macro porous system are described. Amorphous nanoparticles in bimodal aluminosilicates were directly transformed into highly crystalline nanosized zeolites, as well as acting as scaffold template. All pores on three length scales incorporated in one solid body are interconnected with each other. These zeolitic nanocrystal aggregates with hierarchically micro–meso–macroporous structure were thoroughly characterized. TEM images and 29Si NMR spectra showed that the amorphous phase of the initial material had been completely replaced by nanocrystals to give a micro–meso–macroporous crystalline zeolitic structure. Catalytic testing demonstrated their superiority due to the highly active sites and the presence of interconnected micro–meso–macroporosity in the cracking of bulky 1,3,5‐triisopropylbenzene (TIPB) compared to traditional zeolite catalysts. This synthesis strategy was extended to prepare various zeolitic nanocrystal aggregates (ZSM‐5, Beta, TS‐1, etc.) with well‐organized hierarchical micro–meso–macroporous structures.

Islanding detection is a absolutely necessary function for Photovoltaic Grid-Connected Inverters and it is very important to detect the islanding accurately and quickly with less adverse impact on power quality. This paper proposes a positive feedback intermittent active frequency drift method which can decrease the adverse impact of frequency disturbance effectively within the time restrict of islanding detection according to that of traditional islanding detection methods. The theoretical analysis and simulation results show that this algorithm which is simple, effective, fast and have less adverse impact on power quality and has certain application value.

A MPPT (Maximum Power Point Tracking) control method of PV (Photovoltaic) generation system is proposed based on the shortcoming of the existing MPPT algorithms. The method applies CVT (Constant Voltage Tracking) algorithm to adjust the working point of PV array near the MPP (Maximum Power Point) for fast tracking when working point is far from MPP, and uses adapting duty cycle perturb method to optimize the steady state characteristic of MPP for effectively eliminate the output power oscillation under the setting precision. Its model is established and simulated with Matlab/Simulink.The CVT, duty cycle method and proposed methods are simulated respectively and simulation results show that, the proposed method tracks the MPP exactly and quickly and improves the energy conversion efficiency of PV generation system by eliminate the output power oscillation around MPP. Its fast response speed improves the static and dynamic performance of photovoltaic power system.

A field experiment was conducted to remove the potential eutrophication effect of N and P from rural wastewater (RW) during the whole rice growing season of 2010. Commercial fertilizer and RW were applied to furnish 40 kg P ha-1except CK. Results showed TN concentration of the floodwater in the paddy wetland system decreased quickly after transplanting, rosed significantly (P = 0.05) after two N topdressings, and then decreased gradually as the following sequences: SW > GW > DW > BW > CK. Total P (TP) concentration had significantly declined after P application, from October 15 there were no significant increases in TP concentration in the floodwater. Meanwhile, the yield for CK was significantly less (P =0.05) than SW, GW, DW, and BW, with the yield of BW significantly greater (P = 0.05) than other treatments. It is feasible to remove N and P from RW by the paddy wetland system and can be widely used to improve the yield of rice.

The comprehensive assessment of environmental quality is useful for comparison of environmental quality and identification of pollution trends. In the comprehensive assessment methods, many studies proved that grey clustering method is accurate and effective. However, the zero-weight problem occurs in the traditional grey clustering method (TGCM). This flaw may lead to the assessment result distortion. To solve this problem, this paper proposes a modified grey clustering method (MGCM) in which the linear whitening functions in the traditional grey clustering method is replaced by exponential functions. The modified method was applied to assess water quality of four monitoring sections in the Yuhang section of the Tiaoxi River. Then, the results were compared with those obtained with the TGCM. The comparisons show that solving the zero-weight problem can lead to different assessment results and the MGCM is effective to solve the zero-weight problem. The MGCM is more accurate than the TGCM.

In this paper, the effect of the non-uniformity settlement of ground foundation on the upper frame structure is studied. It takes a four-story space frame structure with two spans as an example. The different pedestals are installed at the joint of column footing, which respectively form the fixed supported model and the elastic supported model. Basin shaped settlement is applied in each model. The result shows that the beams are principally suffered with the bending moment and the columns principally suffered with axial force, shear force and bending moment, and that the elastic support model has certain economy.

A mesostructured zirconium oxide was synthesized hydrothermally using cetyltrimethylammonium bromide (CTAB) as the structure-directing agent and ZrSO4. 4H2O as the reactant. Subsequent post-synthetic treatment with H3PO4 followed by the treatment with AlCl3 solutions resulted in mesoporous Zr-P-Al materials, which exhibited high BET specific surface area before calcination. The phosphoric acid concentration affected the textual data of the resulting Zr-P and Zr-P-Al materials greatly. 0.1-0.5 M H3PO4 increased obviously the long-range order of the as-synthesized Zr-P materials while 0.76 M H3PO4 decreased it. After calcination at 773 K, the Zr-P materials turned to nonporous materials except the one synthesized by 0.5 M H3PO4, which showed micropores with a BET specific surface area of 147 m2/g. Further treating the Zr-P materials (synthesized from different concentration of phosphoric acid) with the same amount of AlCl3 solution resulted in mesoporous Zr-P-Al materials, but the long-range order of which decreased when the H3PO4 concentration increased. Similarly, the BET specific surface area of the above-mentioned Zr-P-Al materials decreased from 462 m2/g for 0.25 M H3PO4 to 394 m2/g for 0.5 M H3PO4 and finally to 332 m2/g for 0.76 M H3PO4 after calcination at 773 K, while the pore size increased gradually from 3.0 to 3.5 nm. It was found that about 90% of the CTAB had been removed during the AlCl3 treatment and that the as-synthesized Zr-P-Al materials exhibited high BET specific surface area as well as mesopores. The AlCl3 amount is another factor affecting the textual data of the uncalcined Zr-P-Al materials besides the H3PO4 concentration. With the phosphoric acid concentration of 0.25 M, the BET specific surface area of the as-synthesized Zr-P-Al materials increased from 477 m2/g to as high as 734 m2/g with the increasing AlCl3 amount before it decreased from then on.

In this study, aerodynamic forces on a bridge pylon are investigated by three-dimensional computational fluid dynamics using Large eddy simulation (LES) technology. The main objective is to identify the wind load parameters of the pylon and examine the accuracy of LES model applied to the bluff-body flows. The numerical results were compared with the available wind tunnel test results. Also, a comparison between using LES and Reynolds averaged Navier-Stokes equations with the RNG model have been made. It is found that the LES model competes the RNG model in accuracy for predictions of aerodynamic forces on the pylon.

The results of unsteady Reynolds averaged Navier-Stokes (URANS) simulations of flow around a square cylinder using two-dimensional hybrid meshes were presented in this paper. The first part examined the accuracy of various RANS turbulence models, i.e. the standard model, RNG model, realizable model, standard model, SST model, and RSM, by comparing their results with available experimental data. Despite the limits imposed by the RANS approach and the relatively inexpensive two-dimensional computations, the main features of this complex flow can be predicted reasonably well. Among the computations using various RANS models compared here, the SST model shows the best agreement with the experiment. The second part investigated the effects of corner cutoffs on unsteady flow characteristics around a square cylinder by using the SST model. Especially the detailed near-surface flow structure around the cylinder was focused on, aiming at giving an explanation for the drastic modification of the aerodynamic characteristics as the corner shape is slightly changed.

A five-coordinate mononuclear Dy(III) complex with a C4vgeometry (square-pyramid), [Dy(X)(DBP)2(TMG(H))2] [X = 3-(methylthio)-1-propoxide, DBP = 2,6-di-tert-butylphenoxide, and TMG(H) = 1,1,3,3-tetramethylguanidine] (1), was designed and synthesized. The complex displays a large anisotropy barrier of 432 cm–1in the absence of a dc magnetic field benefiting from the strong interaction between the phenolate and Dy(III) ion. Ab initiocalculations reveal that the most possible relaxation pathway is going through the second excited state. The terminal SMe group in the apical position furnishes the possibility of depositing it on the Au surface by the strong Au–S bond.

A near‐trench paddy field experiment with five urea application rates (0–360 kg N ha−1in 90‐kg increments) was conducted on a paddy soil in the Taihu Lake Region of China to elucidate N losses through lateral seepage during three rice (Oryza sativaL.) growing seasons. The total N (Nt), NH4+–N, and NO3−‐N concentrations in the lateral seepage water increased with increasing N rates. The seasonal Ntfluxes by lateral seepage varied from 6.8 to 25.6 kg N ha−1for urea application rates of 90 to 360 kg N ha−1Lateral seepage accounted for 4.7 to 6.6% of the Ntapplied, implying that lateral seepage was an important pathway of N loss from near‐trench paddy fields. The cumulative N loss via lateral seepage was significantly related to N fertilization rate (P= 0.05). Floodwater level was also identified as a main factor affecting N losses via lateral seepage from paddy fields, as indicated by a positive linear relationship (R2= 0.43) between floodwater level and daily lateral flow during the flooded period (P= 0.05). Under the conditions of these experiments, a shallow floodwater depth of 50 mm, urea application rates of 90 kg N ha−1or less, and no rainfall within 1 wk after N application reduced N losses by lateral seepage from paddy fields.

Electricity consumption increases rapidly with the rapid development of China. The environmental damage costs of electricity generation are very important for both policy analysis and the proper management of the environment. A method was developed in this work to estimate gross environmental damage costs according to emission inventory and environmental cost factors, and to extend the costs from provincial to national level with population density. In this paper, sulfur dioxide (SO2), nitrogen oxides (NOx), particulate matter less than 10 μm in diameter (PM10), and carbon dioxide (CO2) from fossil fired power plants over 6000 kW were selected as index pollutants to quantify the environmental costs of damages on human health and global warming. With the new developed method, environmental damage costs, caused by 3 types of fired power plants in 30 provinces and 6 economic sectors during the years 2000 to 2003, were evaluated and analyzed. It can be seen that the calculated total national environmental damage costs of electricity have rapidly increased from 94930.87 × 106USD in 2000 to about 141041.39 × 106USD in 2003, with an average annual growth rate of 14.11%. Environmental damage costs of SO2, NOx, PM10, and CO2are 69475.69 × 106, 30079.29 × 106, 28931.84 × 106, and 12554.57 × 106USD and account for 49.26%, 21.33%, 20.51%, and 8.90% of total environmental costs in fossil electricity generation, respectively. With regard to regional distribution, external costs caused by fossil electricity generation are mainly concentrated in the more populated and industrialized areas of China, i.e., the Eastern Central and Southeastern areas.