Negative effect improvement of accelerated curing on chloride penetration resistance of ordinary concrete

Four mineral admixture concrete specimens werefabricated to study the negative effect improvements ofaccelerated curing on the chloride penetration resistance ofordinary concrete. After reaching different initial strengths, the specimens were placed in 40, 60, or 80 t water tanks foraccelerated curing. The Coulomb values of the specimens weemeasured with ASTM C1202 experiment at 28, 100, 200, ad300 d. Partial specimens were also selected for rapid chlorideion migration coefficient and mercury intrusion porosimetryexperiments. The experimental results show that theaccelerated curing for ordinary concrete linealy deterioratesthe chloride penetration resistance, whereas the incorporationof mineral admixtures improves the concrete microscopic pore-structures and negative effects. An upper temperature limit of60 t of the accelerated curing is suitable for obtainingsuperior chloride penetration resistance for the mineraladmixture concrete. Pre-curing at a normal temperature of 20t is beneficial for improving the negative effect, which isalso aieviated with increasing testing age as a result of thesuccessive hydration of binder materials in concrete.

Intelligent Diagnosis of Short Hydraulic Signal Based on Improved EEMD and SVM with Few Low-dimensional Training Samples

The high accurate classification ability of an intelligent diagnosis method often needs a large amount of training samples with high-dimensional eigenvectors, however the characteristics of the signal need to be extracted accurately. Although the existing EMD（empirical mode decomposition） and EEMD（ensemble empirical mode decomposition） are suitable for processing non-stationary and non-linear signals, but when a short signal, such as a hydraulic impact signal, is concerned, their decomposition accuracy become very poor. An improve EEMD is proposed specifically for short hydraulic impact signals. The improvements of this new EEMD are mainly reflected in four aspects, including self-adaptive de-noising based on EEMD, signal extension based on SVM（support vector machine）, extreme center fitting based on cubic spline interpolation, and pseudo component exclusion based on cross-correlation analysis. After the energy eigenvector is extracted from the result of the improved EEMD, the fault pattern recognition based on SVM with small amount of low-dimensional training samples is studied. At last, the diagnosis ability of improved EEMD＋SVM method is compared with the EEMD＋SVM and EMD＋SVM methods, and its diagnosis accuracy is distinctly higher than the other two methods no matter the dimension of the eigenvectors are low or high. The improved EEMD is very propitious for the decomposition of short signal, such as hydraulic impact signal, and its combination with SVM has high ability for the diagnosis of hydraulic impact faults.

An effective technique to improve photosynthetic productivity and adaptability of rice

High photosynthetic productivity and widephotosynthetic adaptability are two importantphysiological characteristics for the sustained highyield and wider growing range of rice.Preliminaryexperiments indicated that the utilization ofbeterosis between two different ecotype rices,US

Improved third-order nonlinear effect in graphene based on bound states in the continuum

The scattering matrix theory has been developed to calculate the third-order nonlinear effect in sphere-grapheneslab structures. By designing structural parameters, we have demonstrated that the incident electromagnetic wave can be well confined in the graphene in these structures due to the formation of a bound state in the continuum(BIC) of radiation modes. Based on such a bound state, third-harmonic(TH) generation and four-wave mixing(FWM) have been studied. It is found that the efficiency of TH generation in monolayer graphene can be enhanced about 7 orders of magnitude. It is interesting that we can design structure parameters to make all beams(the pump beam, probe beam, and generated FWM signal) be BICs at the same time. In such a case, the efficiency of FWM in monolayer graphene can be enhanced about 9 orders of magnitude. Both the TH and FWM signals are sensitive to the wavelength, and possess high Q factors, which exhibit very good monochromaticity. By taking suitable BICs, the selective generation of TH and FWM signals for S-and P-polarized waves can also be realized,which is beneficial for the design of optical devices.

Grey Repairable System Analysis

In this paper, we systematically discuss the basic concepts of grey theory, particularly the grey differential equation and its mathematical foundation, which is essentially unknown in the reliability engineering community. Accordingly, we propose a small-sample based approach to estimate repair improvement effects by partitioning system stopping times into intrinsic functioning times and repair improvement times. An industrial data set is used for illustrative purposes in a stepwise manner.

Review of Modern Research on Toxicity of Traditional Chinese Medicine Aconm Lateralis Radix Praeparaia

The traditional Chinese medicine Aconm Lateralis Radix Praeparaia(Fuzi)is pungent and sweet in taste,hot in nature,and has high toxicity.It governs the meridians of the heart,kidney and spleen.It has the functions of restoring yang to save from collapse,dispersing cold and removing dampness,and warming the middle to relieve pain.It is often used for the treatment of yang collapse,cold limbs,weak pulse,heart yang deficiency,heart pain due to chest impediment,abdominal cold-pain,kidney yang deficiency,impotence and cold in womb,and syndrome of exogenous disease due to yang deficiency,etc.Its great yang qi and strong medicinal properties often bring about toxic and adverse effects.However,after processing or combination with other medicinal materials,the effects of Aconm Lateralis Radix Praeparaia are quite different.Not only the toxicity is greatly reduced,but also the curative effects are strengthened.Through searching related literature,this paper reviewed the researches about the toxicity reduction and curative effect improvement of Aconm Lateralis Radix Praeparaia,in order to provide a certain theoretic reference for future further research of Aconm Lateralis Radix Praeparaia.

Simple and effective method to improve the signal-to-noise ratio of compressive imaging

This Letter presents a simple and effective method to improve the signal-to-noise ratio（SNR） of compressing imaging. The main principles of the proposed method are the correlation of the image signals and the randomness of the noise. Multiple low SNR images are reconstructed firstly by the compressed sensing reconstruction algorithm, and then two-dimensional time delay integration technology is adopted to improve the SNR. Results show that the proposed method can improve the SNR performance efficiently and it is easy to apply the a lgorithm to the real project.

Effect of levothyroxine replacement therapy on improving diffused left ventricular myocardial lesions in patients with hypothyroidism

Objective To study the effect of levothyroxine replacement therapy on improving diffused left ventricular myocardial lesions and cardiac function in patients with hypothyroidism.Methods Our research included 2groups:Hypothyroidism group,n=20,newly diagnosed patients and Control group,n=17,normal healthy subjects.Diffused left ventricular myocardial lesions

Assembled Photosensitizers Applied for Enhanced Photodynamic Therapy

Photodynamic therapy(PDT)has emerged as an efficient method for cancer therapy.However,traditional photosensitizers(PSs)always have low bioavailability.For example,hydrophobic PSs tend to aggregate in cells and lead to aggregation-induced quenching;while hydrophilic PSs that have good solubility in water systems can hardly penetrate into cells whose membranes are lipophilic.To overcome these drawbacks,suitable PSs that meet the requirements of PDT are needed.Numerous investigations have been introduced,especially the molecular-assembly technique that can increase the bioavailability of PSs during the tumor therapy process.Besides,increasing the quantum yield of reactive oxygen species(ROS)by adjusting the PS triplet state lifetime as well as developing aggregation-induced emission(AIE)agents can also improve the PDT effect.This review summarizes the molecular-assembly technique to obtain intelligent PSs to achieve high PDT efficiency.First,increasing the quantum yield of ROS by decreasing the energy gap between S_(1)and T_(1)states or increasing the spin–orbit coupling Hamiltonian are introduced.Second,we present the bioavailability of traditional PSs by improving the amphiphilicity of the PSs or using intelligent nanostructures.Then,the AIE PSs that can form ROS in the aggregated state under irradiation are described.Finally,the perspective and challenges of PDT are discussed.

Nanoelectromechanical resonant narrow-band amplifiers

This study demonstrates amplification of electrical signals using a very simple nanomechanical device.It is shown that vibration amplitude amplification using a combination of mechanical resonance and thermal-piezoresistive energy pumping,which was previously demonstrated to drive self-sustained mechanical oscillation,can turn the relatively weak piezoresistivity of silicon into a viable electronic amplification mechanism with power gains of 420 dB.Various functionalities ranging from frequency selection and timing to sensing and actuation have been successfully demonstrated for microscale and nanoscale electromechanical systems.Although such capabilities complement solid-state electronics,enabling state-of-the-art compact and high-performance electronics,the amplification of electronic signals is an area where micro-/nanomechanics has not experienced much progress.In contrast to semiconductor devices,the performance of the proposed nanoelectromechanical amplifier improves significantly as the dimensions are reduced to the nanoscale presenting a potential pathway toward deep-nanoscale electronics.The nanoelectromechanical amplifier can also address the need for ultranarrow-band filtering along with the amplification of lowpower signals in wireless communications and certain sensing applications,which is another need that is not efficiently addressable using semiconductor technology.