论唐宋诗文中的疏广、疏受形象

西汉疏广、疏受简称“二疏”,他们作为功成身退的代表之一,其典型意义与范式价值在唐宋诗文中多有展现。在题咏方式上,唐宋诗文中的“二疏”往往单提与并提互存,且出现“二疏”与“四皓”、陶渊明等人的固定组合。“二疏”在唐宋诗文中的形象意蕴,可从进退两个角度进行阐释,进为聪明睿智、功勋卓著的能臣,退为知足见机、流芳千古的“明士”。至于唐宋诗文题咏“二疏”的原因,则主要与崇隐思想的提倡及影响、致仕观念的普及与认同、三教融通的驱动和互补之用密切相关。

Microstructural, wettability, and corrosion behaviour of TiO_(2) thin film sputtered on aluminium

The study investigated the application of radiofrequency(RF)-sputtered TiO2 coatings at various temperatures to enhance the hydrophobicity and corrosion resistance of Al6061 alloy.The research aimed to establish a correlation between the coating process and the resulting surface properties.Surface roughness and wettability were quantified with a surface profilometer and goniometer.Additionally,chemical boiling and salt spray corrosion tests were conducted to evaluate any topographical changes during these procedures.The analysis further involved the use of field-emission scanning electron microscopy(FESEM),energy-dispersive spectroscopy(EDS),and X-ray diffraction(XRD)techniques to characterize the deposited coatings.The findings indicated that the TiO2 coating applied at 500℃exhibited the highest water contact angle and superior corrosion resistance compared to other temperatures.Surface characterization confirmed that this specific TiO_(2) coating at 500℃ effectively delays corrosion due to its hydrophobic behavior,making it durable for industrial applications.

Comparison of Phycobiliproteins from Gracilaria lemaneiformis (Rhodophyceae) and Its Pigment Mutants in Spectral and Molecular Respects

Comparative studies of absorption spectra of phycobiliproteins of Gracilaria lemaneiformis Greville and its pigmental mutants were conducted in this study. The results showed that the absorption spectra of phycoerythrins ( PE) from different material changed significantly, while those of phycocyanins (PC) and allophycocyanins (APC) were basically similar. In order to disclose the essence of die difference, partial sequences of die subunit genes of PE of Qingdao strain of G. lemaneiformis (qd) and its pigmental mutants were determined. The amino acid sequences were deduced and used to explain spectral shifts of PE from the pigmental mutants. The amino acid sequences of PE resembled each other, and several residues changed among qd and its pigmental mutants. Residue substitutions were found in a region consisting of amino acids which determined are secondary structure and subunits interactions, thus might influence the confirmation and interaction of subunits, and further caused spectral deviation.

Ground-roll separation of seismic data based on morphological component analysis in twodimensional domain

Ground roll is an interference wave that severely degrades the signal-to-noise ratio of seismic data and affects its subsequent processing and interpretation.In this study,according to differences in morphological characteristics between ground roll and reflected waves,we use morphological component analysis based on two-dimensional dictionaries to separate ground roll and reflected waves.Because ground roll is characterized by lowfrequency,low-velocity,and dispersion,we select two-dimensional undecimated discrete wavelet transform as a sparse representation dictionary of ground roll.Because of a strong local correlation of the reflected wave,we select two-dimensional local discrete cosine transform as the sparse representation dictionary of reflected waves.A sparse representation model of seismic data is constructed based on a two-dimensional joint dictionary then a block coordinate relaxation algorithm is used to solve the model and decompose seismic record into reflected wave part and ground roll part.The good effects for the synthetic seismic data and application of real seismic data indicate that when using the model,strong-energy ground roll is considerably suppressed and the waveform of the reflected wave is effectively protected.

《月喜疏》与“二指喻”——古印度胜论哲学之谜考释

《月喜疏》是现存最早的《胜论经》注释文献,反映了古典时期的胜论哲学。自1961年梵本首次刊布以来,引起了国外学界的广泛研究,但由于古典胜论学派的传世文献极少,该疏的形成年代一直众测纷纭。笔者在阅读佛教学者清辩的《思择焰》时,注意到其中多次引述的"二指喻"只见于《月喜疏》,而不存在于其他胜论文献中。本文在利用《月喜疏》相关内容解读《思择焰》"二指喻"之谜的同时,以清辩为时代坐标,推定月喜的鼎盛年约在公元500—530年,由此也一并回应了印度哲学史上的两个重要问题。

Geophysical data sparse reconstruction based on L0-norm minimization

Missing data are a problem in geophysical surveys, and interpolation and reconstruction of missing data is part of the data processing and interpretation. Based on the sparseness of the geophysical data or the transform domain, we can improve the accuracy and stability of the reconstruction by transforming it to a sparse optimization problem. In this paper, we propose a mathematical model for the sparse reconstruction of data based on the LO-norm minimization. Furthermore, we discuss two types of the approximation algorithm for the LO- norm minimization according to the size and characteristics of the geophysical data： namely, the iteratively reweighted least-squares algorithm and the fast iterative hard thresholding algorithm. Theoretical and numerical analysis showed that applying the iteratively reweighted least-squares algorithm to the reconstruction of potential field data exploits its fast convergence rate, short calculation time, and high precision, whereas the fast iterative hard thresholding algorithm is more suitable for processing seismic data, moreover, its computational efficiency is better than that of the traditional iterative hard thresholding algorithm.

Susceptible-Infected-Recovered-Susceptible Virus Spreading Model Based on Two Dimensional Sparse Lattice

In order to clarify the virus＇ spreading rules, a SIRS （Susceptible-Infected-Recovered-Susceptible） disease spread model based on sparsely distributed crowd is proposed. In this model, the effects of crowd-density, spread efficiency and the moving of individuals on the spreading of viruses are researched. The theoretical analysis and analog simulation shows that there exist a critical value, only when the product of spread efficiency and crowd density goes beyond the critical value, can viruses spread in crowd continuously and steadily. Besides, the moving of individuals can promote the spreading of viruses. These results are helpful guiding people to defense and control virus＇ spreading process.

Nonequidistant two-dimensional antenna arrays based on magic squares

New methods of synthetizing nonequidistant sparse antenna arrays based on the properties of magic squares are studied.The methods of construction and algorithms of synthesis of two-dimensional antennas based on them providing a high degreeof dilution and sufficiently small side radiation are proposed.The methods for construction of such antennas and their maincharacteristics are considered.

Effects of Ionic Surfactants on Bacterial Luciferase and α-Amylase

In order to study the effects of ionic surfactants on bacterial luciferase,the cationic surfactant dodecyltrimethylammonium biomide (DTAB) and anionic surfactant sodium dodecylsulfate (SDS) were chosen.For comparison with bacterial luciferase,α-amylase was used since these two enzymes have similar electrostatic potential and charged active sites.After the enzymes were treated with the surfactants,the catalytic properties of bacterial luciferase andα-amylase were assayed,and fluorescence spectroscopy and circular dichroism (CD) were used to analyze the alteration of the protein structure.The results showed that when the DTAB concentration was low,the cationic surfactant DTAB enhanced the enzymatic activities of bacterial luciferase andα-amylase.On the other hand,the anionic surfactant SDS did not alter the enzymatic activity.The main interaction of cationic surfactant DTAB and the negatively charged surface of the proteins was the ionic interaction,which could alter the environment for the enzyme to work when the DTAB/enzyme molar ratio was low.However,at high cationic surfactant concentration,the ionic interaction and hydrophobic interaction might destroy the secondary and tertiary structures of the proteins,leading to the loss of enzymatic activities.

Adsorption and flotation mechanism of a ketoxime-dithiocarbonate surfactant to chalcopyrite

The adsorption mechanism of O-isopropyl-S-[2-(hydroxyimino) propyl] dithiocarbonate ester(IPXPO) to chalcopyrite was investigated by using contact angle, in-situ atomic force microscopy(in-situ AFM), cyclic voltammetry(CV) and X-ray photoelectron spectroscopy(XPS). The results of contact angle and in-situ AFM demonstrated that IPXPO adsorbed on chalcopyrite increases surface hydrophobicity and roughness. It was found by CV experiments that a layer passive film was formed. The results of XPS spectra further revealed that the thiol S atom, oxime N atom, and O atom in the IPXPO molecule might react with copper atoms to form Cu-S, Cu-N, and Cu-O bonds, respectively. An artificial mixed minerals flotation test indicated that under the condition of pH=6.79 and IPXPO initial concentration 5×10^(-5)mol/L, the flotation recovery of chalcopyrite reached about 90%, while for pyrite only 25%, suggesting that IPXPO is an excellent collector for flotation separation and enrichment of chalcopyrite.

Percutaneous estrogen in prevention of early postmenopausal bone loss in Chinese women

OBJECTIVE: To identify the optimal dosage of 17beta-estradiol gel + oral progestin for preventing bone loss in postmenopausal Chinese women. METHODS: A 3-year open label, randomized, prospective clinical trial was conducted. Sixty healthy women who had been postmenopausal for 1 to 5 years were recruited and divided into following 4 groups: group 1, percutaneous gel 17beta-estradiol (E(2)) 1.5 mg/d plus micronized progesterone (MP) 100 mg/d; group 2, percutaneous gel 17beta-estradiol (E(2)) 1.5 mg/d plus medroxyprogesterone acetate (MPA) 2 mg/d; group 3, percutaneous gel 17beta-estradiol (E(2)) 0.75 mg/d plus micronized progesterone (MP) 100 mg/d; and group 4, percutaneous gel 17beta-estradiol (E(2)) 0.75 mg/d plus medroxyprogesterone acetate (MPA) 2 mg/d. Estrogen and progestin were given continuously for 25 days per month. Bone mineral density (BMD) was measured using quantitative computed tomography (QCT) for trabecular bone of L2-5 and dual energy X-ray absorptiometry (DEXA) for L2-4 and hip 5 times during the trial at baseline and at the 6-, 12-, 18-, 24- and 36-month visits. RESULTS: Fifty-nine patients (98.3%, 59/60) stayed in the study for 1 year, 56 patients (93.3%, 56/60) for 2 years, and 51 (85%, 51/50) for 3 years. On average, menopausal symptoms were relieved by 80% after 6 months of treatment. By the 24th month, the mean increase in BMD ranged from 4.3% to 7.5% in trabecular bone; and by the 36th month, it ranged from 4.2% to 6.2% in L2-4 and 1.61% to 3.77% in the neck. There were significant difference after treatment (P 0.05) was found in improvement of symptoms, levels of bone markers or BMD. CONCLUSION: A daily dose of estradiol gel, either 0.75 mg or 1.5 mg, is effective in preventing early postmenopausal bone loss and relieving menopausal symptoms. After 3-year treatment, spinal BMD could increase steadily, so does hip BMD, especially in the first 2 years.

Hybrid photoanode films based on sparse ZnO rod array-TiO_2 nanoparticles in dye-sensitized solar cells

ZnO-TiO2 hybrid photoanodes were fabricated via the doctor-blade method by integrating vertically-grown sparse ZnO arrays with hydrothermal TiO2 nanoparticles. A special surface-coating technique was developed to deposit a thin TiO2 layer on the surface of ZnO rods. Microstructure, optical and photoelectrochemical performance of the hybrid photoanodes were investigated. The denser ZnO array exhibited bad filling behavior of nanoparticles in the interspace of ZnO rods, strong scattering and low conversion efficiency (0.27%). The sparser array showed a much better integrated microstructure, improved transmittance and high conversion efficiency (2.68%). The surface modification of ZnO rods by the TiO2 thin layer was found useful in improving the interfacial microstructure between the ZnO rod and the TiO2 bulk film, and the total conversion efficiency of 3.01% was achieved, higher than that of the pure TiO2 nanoparticle cell (2.93%). The increased scattering effects on the incident light, the enhanced electron transportation at TiO2/dye/electrolyte interface, and the inhabited recombination were responsible for this improvement.

Two-scale sparse finite element approximations

To reduce computational cost,we study some two-scale finite element approximations on sparse grids for elliptic partial differential equations of second order in a general setting.Over any tensor product domain ?R^d with d = 2,3,we construct the two-scale finite element approximations for both boundary value and eigenvalue problems by using a Boolean sum of some existing finite element approximations on a coarse grid and some univariate fine grids and hence they are cheaper approximations.As applications,we obtain some new efficient finite element discretizations for the two classes of problem:The new two-scale finite element approximation on a sparse grid not only has the less degrees of freedom but also achieves a good accuracy of approximation.

Efficient removal of chlorophenols from water with a magnetic reduced graphene oxide composite

A magnetic reduced graphene oxide composite(MRGO) was successfully prepared by a simple and green method. MRGO was then used as an adsorbent and found to exhibit enhanced removal efficiency for various chlorophenols(CPs) from water compared with its precursors, graphene oxide(GO) and reduced graphene oxide. The CPs were o-chlorophenol, p-chlorophenol, 2,4-dichlorophenol, and 2,4,6-trichlorophenol. Among them, 2,4,6-trichlorophenol, which exhibited the lowest water solubility and highest molecular weight, most easily bound to MRGO. The preferential interactions between MRGO and CPs were hydrophobic interactions(?-? stacking and hydrophobic effect). This result was confirmed by the equilibrium adsorption behavior in which isotherms were all well described by Freudlich model, indicating heterogeneous and multilayer adsorption. Therefore, CP adsorption was more favored under neutral and acidic conditions, and the decreased removal efficiency of MRGO at higher p H levels was due to the improved hydrophilicity of CPs for deprotonation effect. Moreover, MRGO showed fast removal of each CP, achieving adsorption equilibrium within 10.0 min, presented efficient separation from water under an external magnetic field, and was easily regenerated using dilute Na OH aqueous solution after reaching saturated adsorption. Adsorption capacity of the regenerated MRGO had almost no loss until after five cycles. In summary, MRGO was an efficient adsorbent for the removal of various CPs and had considerable application potential in water treatment.

Superhydrophobic conductive rubber band with synergistic dual conductive layer for wide-range sensitive strain sensor

Wearable electronic devices have received increasing interests because of their excellent flexibility,stretchability,and human friendliness.As the core components,flexible strain sensors integrated with wide working range,high sensitivity,and environment stability,especially in moisture or corrosive environments,remain a huge challenge.Herein,synergistic carbon nanotubes(CNTs)/reduced graphene oxide(rGO)dual conductive layer decorated elastic rubber band(RB)was successfully developed and treated with hydrophobic fumed silica(Hf-SiO_(2))for preparing superhydrophobic strain sensor.As expected,stable entangled CNTs layer and ultrasensitive microcracked rGO layer endow the sensor with extremely low detection limit(0.1%),high sensitivity(gauge factor is 685.3 at 482%strain),wide workable strain range(0–482%),fast response/recovery(200 ms/200 ms)and favorable reliability and reproducibility over 1000 cycles.Besides,the constructed Hf-SiO_(2) coating also makes the sensor exhibit excellent superhydrophobicity,self-cleaning property,and corrosion-resistance.As a proof of concept,our prepared high-performance strain sensor can realize the full-range monitoring of human motions and physiological signals even in the water environment,including pulse,vocalization,joint bending,running,and gesture recognition.Interestingly,it can also be knitted into a tactile electronic textile for spatial pressure distribution measurement.Thus,this study provides a universal technique for the preparation of high-performance strain sensors with great potential applications in the field of next-generation intelligent wearable electronics.

SOME PROPERTIES OF LSQR FOR LARGE SPARSE LINEAR LEAST SQUARES PROBLEMS

It is well-known that many Krylov solvers for linear systems,eigenvalue problems,andsingular value decomposition problems have very simple and elegant formulas for residual norms.Theseformulas not only allow us to further understand the methods theoretically but also can be usedas cheap stopping criteria without forming approximate solutions and residuals at each step beforeconvergence takes place.LSQR for large sparse linear least squares problems is based on the Lanczosbidiagonalization process and is a Krylov solver.However,there has not yet been an analogouslyelegant formula for residual norms.This paper derives such kind of formula.In addition,the authorgets some other properties of LSQR and its mathematically equivalent CGLS.

Sparse bivariate polynomial factorization

Motivated by Sasaki＇s work on the extended Hensel construction for solving multivariate algebraic equations, we present a generalized Hensel lifting, which takes advantage of sparsity, for factoring bivariate polynomial over the rational number field. Another feature of the factorization algorithm presented in this article is a new recombination method, which can solve the extraneous factor problem before lifting based on numerical linear algebra. Both theoretical analysis and experimental data show that the algorithm is etIicient, especially for sparse bivariate polynomials.