响应面优化棉秆基活性炭的制备及其吸附性能研究

以棉花秸秆为原料、ZnCl_(2)/AlCl_(3)为改性剂制备活性炭(AC)。利用中心复合设计法(CCD)对主要影响因子进行参数优化,并利用预测模型确定最佳制备工艺为:活化温度为640℃、浸渍质量比(棉秸秆与改性剂的质量比)为1.58∶1、活化时间为87 min、改性剂配比(改性剂中ZnCl_(2)与AlCl_(3)的质量比)为9∶1。在实际实验条件下,样品得率、总酸含量分别为44.32%、0.87mmol/g,与模型预测值误差分别为1.79%、1.04%。利用碱性有机染料甲基紫研究其吸附性能,当活性炭投加量为1.18 g/L、溶液质量浓度为82.00 mg/L时,其对甲基紫去除率均能达到90%以上。ZnCl_(2)/AlCl_(3)改性棉秸秆基活性炭具有良好的吸附性能,为棉秸秆的应用提供了参考依据。

活化剂改性秸秆基活性炭的制备及其表征

研究活化剂改性棉花秸秆在制备活性炭(AC)过程中的最优工艺。通过Design Expert 8.0软件建立活化条件与活性炭持水性能参数间的量化关系,研究AC在不同活化温度、活化时间、浸渍比和活化剂配比条件下持水性能的变化规律。利用扫描电镜(SEM)、傅里叶变换红外光谱、比表面积及孔径大小对AC的结构及组成进行表征分析。结果表明:活化剂配比是对AC持水性能影响显著的因子;最佳工艺条件为活化温度640.70℃、浸渍比1.58∶1、活化时间87.27 min、活化剂配比9.02∶1。在此条件下制得AC持水性能为2.551 g/g,与预测值(2.52 g/g)误差为1.24%,表明该模型用于棉秆基活性炭工艺优化实用价值较高。

Partially crystallized Pd nanoparticles decorated TiO_2 prepared by atmospheric-pressure cold plasma and its enhanced photocatalytic performance

TiO2 decorated with partially crystallized Pd nanoparticles （Pd/TiO2-P） was successfully prepared by atmospheric-pressure dielectric barrier discharge cold plasma. The XRD and XPS analyses proved that Pd ions were reduced to partially crystallized metallic Pd nanoparticles in Pd/TiO2-P. The XPS spectra also indicated that an enhanced metal-support interaction was formed due to the existence of partially crystallized Pd nanoparticles with lower coordination number in Pd/TiO2-P. Photocatalytic activity of Pd/TiO2-P was much higher than that of TiO2 samples decorated with well crystallized Pd nanoparticles.

Multiple Endmember Hyperspectral Sparse Unmixing Based on Improved OMP Algorithm

In conventional linear spectral mixture analysis model,a class is represented by a single endmember.However,the intra-class spectral variability is usually very large,which makes it difficult to represent a class,and in this case,it leads to incorrect unmixing results. Some proposed algorithms play a positive role in overcoming the endmember variability,but there are shortcomings on computation intensive,unsatisfactory unmixing results and so on. Recently,sparse regression has been applied to unmixing,assuming each mixed pixel can be expressed as a linear combination of only a few spectra in a spectral library. It is essentially the same as multiple endmember spectral unmixing. OMP( orthogonal matching pursuit),a sparse reconstruction algorithm,has advantages of simple structure and high efficiency. However,it does not take into account the constraints of abundance non-negativity and abundance sum-to-one( ANC and ASC),leading to undesirable unmixing results. In order to solve these issues,this paper presents an improved OMP algorithm( fully constraint OMP,FOMP) for multiple endmember hyperspectral sparse unmixing. The proposed algorithm overcomes the shortcomings of OMP,and on the other hand,it solves the problem of endmember variability.The ANC and ASC constraints are firstly added into the OMP algorithm,and then the endmember set is refined by the relative increase in root-mean-square-error( RMSE) to avoid over-fitting,finally pixels are unmixed by their optimal endmember set. The simulated and real hyperspectral data experiments show that FOPM unmixing results are ideally comparable and abundance RMSE reduces much lower than OMP and simple spectral mixture analysis( s SMA),and has a strong anti-noise performance. It proves that multiple endmember spectral mixture analysis is more reasonable.

Improved Algorithm for Solving Discrete Logarithm Problem by Expanding Factor

The discrete logarithm problem(DLP)is to find a solution n such that g^n=h in a finite cyclic group G=,where h∈G.The DLP is the security foundation of many cryptosystems,such as RSA.We propose a method to improve Pollard’s kangaroo algorithm,which is the classic algorithm for solving the DLP.In the proposed algorithm,the large integer multiplications are reduced by controlling whether to perform large integer multiplication.To control the process,the tools of expanding factor and jumping distance are introduced.The expanding factor is an indicator used to measure the probability of collision.Large integer multiplication is performed if the value of the expanding factor is greater than the given bound.The improved algorithm requires an average of(1.633+o(1))q(1/2)times of the large integer multiplications.In experiments,the average large integer multiplication times is approximately(1.5+o(1))q(1/2).

Determination of the Amplification Factor for 2-Hydroxy-ethylperoxy Radicals in PERCA

A new method is proposed to determine the amplification factor for 2-hydroxy ethylperoxy radicals （HOC2H4O2·） in chemical amplifier. The radical source comes from the reaction of excess ethene with HO· radicals generated in the photolysis of water vapor at the wave length of 185 nm in air in a flow tube. This produces a radical source which contains equal amount of HO2·and HOC2H4O2·. The amplification factor is derived from the slopes of the lines between produced NO2 in chemical amplifier and total initial radical concentrations measured for the source of HO2· and that of the same amount of HO2· and HOC2H4O2· respectively. The amplification factor of HOC2H4O2· was similar to that of HO2·, indicating that HOC2H4O2· can be measured with the same sensitivity as HO2· by chemical amplifier.

Possible Candidates for Chirality in the Odd-Odd As Isotopes

The deformations and the corresponding configurations of the odd-odd As isotopes are investigated using the adiabatic and configuration-fixed constrained triaxial relativistic mean field(RMF)theory.Energy minima with triaxial deformations and high-j particle-hole configurations are obtained in 72,74,76,78,80As,where the chiral doublet bands are possible to appear.The existence of multiple chiral doublet(MχD)is demonstrated in 74,76,78As.Based on the calculated single-particle levels,we also find possible coexistence of chiral and pseudospin symmetries in the odd-odd As isotopes.

Alternating Parity Band in Octupole-Soft ^(140)Xe with Axial Vibrational-Rotational Model and Triaxial Rigid Rotor Model

Energies of the yrast positive-and negative-parity excited states in140 Xe are reproduced by two different models considering quadrupole-octupole deformations, namely the axial vibrational-rotational model and the triaxial rigid rotor model, and compared with the stable octupole-deformed222 Th. The origin of the energy difference between the opposite parity sequences is considered from two different mechanisms, the vibration in axial deformed energy minima and the rotation considering the effective triaxial deformation. The success of reproducing the data in both the models implies that these two mechanisms are equivalent on some level for the octupole-soft nuclei. By investigating the probability distributions for projection of total angular momentum in the triaxial rigid rotor model, it is found that such an energy difference is associated with the difference of orientation of the rotational axis.

A key factor to the spin parameter of uniformly rotating compact stars: crust structure

We study the dimensionless spin parameter j ≡ cJ/（GM2） of different kinds of uniformly rotating compact stars, including traditional neutron stars, hyperonic neutron stars and hybrid stars, based on relativistic mean field theory and the MIT bag model. It is found that j ~ 0.7, which had been suggested in traditional neutron stars, is sustained for hyperonic neutron stars and hybrid stars with M 〉 0.5 MG. Not the interior but rather the crust structure of the stars is a key factor to determine jmax for three kinds of selected compact stars. Furthermore, a universal formula j = 0.63（f/fK） -- 0.42（f/fK）2 ＋ 0.48（f/fK）z is suggested to determine the spin parameter at any rotational frequency f smaller than the Keplerian frequency fK.

Kansei Engineering Analysis of Purple-clay Teapot Based on Online Comment Data

Product form has become an important communication medium between designers and consumers.Therefore,the collection and analysis of consumer evaluation of products can provide an important reference index for product form design.In this paper,purpleclay teapot was taken as an example and comments of Tmall consumers were collected through web crawler,and the product image vocabulary was extracted to analyze the needs of users.Using the research method of Kansei Engineering,the semantic space of the modeling and image of purple-clay teapot was established,and the relationship between the modeling elements and the image of purple-clay teapot was searched,which could provide valuable reference for the modeling design of purple-clay teapot.

Experimental studies for nuclear chirality in China

In the last decade,chiral symmetry in atomic nuclei has attracted significant attention and become one of the hot topics in current nuclear physics frontiers.This paper provides a review of experimental studies for nuclear chirality in China.In particular,the experimental setups,chiral mass regions,lifetime measurements,and simultaneous breaking of chirality and other symmetries are discussed in detail.These studies found a new chiral mass region(A≈80),extended the boundaries of the A≈100 and 130 chiral mass regions,and tested the chiral geometry of^(130)Cs,^(106)Ag,^(80)Br and^(76)Br by lifetime measurements.In addition,simultaneous breaking of chirality and other symmetries have been studied in^(74)As,^(76)Br,^(78)Br,^(80)Br,^(81)Kr and^(131)Ba.

低温脱脂大豆粕的低丰度蛋白提取和高丰度蛋白去除条件的优化（英文）

目的:优化低温脱脂大豆粕中的低丰度蛋白提取和高丰度蛋白去除条件,为进一步探讨大豆低丰度蛋白对动物的生理功能影响提供试验材料。创新点:结合提取时间和异丙醇浓度,将超声波(超声时间、功率)用于辅助异丙醇去除大豆高丰度蛋白和富集低丰度蛋白的研究。方法:在单因素试验基础上,设计了超声时间、超声功率、提取时间和异丙醇浓度等四因素三水平的正交试验。并通过测定提取液中的蛋白浓度和通过聚丙烯酰胺凝胶电泳(SDS-PAGE)、质谱分析(MS)等蛋白质组学手段鉴定提取液或丙酮沉淀物中的蛋白质含量,实现了大豆高丰度蛋白去除和低丰度蛋白提取条件的优化。结论:50%异丙醇,350 W超声15 min,提取1 h是大豆低丰度蛋白提取的最佳条件。提取物含多种低丰度蛋白(油质蛋白、大豆未知蛋白、磷酸酯D和无特征大豆蛋白),且无大豆高丰度蛋白(大豆球蛋白和β-伴大豆球蛋白)。

Design of layered-stacking graphene assemblies as advanced electrodes for supercapacitors

Graphene is a competitive electrode material for supercapacitors due to its unique two-dimensional structure,large surface area,high conductivity,and good physicochemical stability.However,random agglomeration and restacking of graphene sheets result in a reduced surface area and a loose structure with low density,which severely restricts the application for high gravimetric/volumetric energy density devices.Rational design of the layered-stacking structure of graphene assemblies can effectively prevent the restacking of graphene sheets,construct efficient ion transport channels,and improve spatial utilization,demonstrating the huge potential for developing advanced electrode materials.Herein,from the aspect of improving the electrochemical kinetics through designing efficient electron and ion transport paths,we first highlight the advantages of layered-stacking graphene assemblies,describe some common routes for preparing graphene building units,and then summarize the novel methods to design layered-stacking structures.A comprehensive review of the typical structure including nanocarbon pillared graphene,porous graphene blocks,and graphene ribbon films is provided with a focus on the mechanisms behind the performance improvements.Finally,critical challenges and some general ideas for future development are proposed,which may open up new opportunities for material chemistry and device innovation.

Purification and Identification of a Novel Protein Isolated from Panax quinquefolium and Evaluation of its In vitro Antioxidant Properties

Objective:A novel protein was first purified from Panax quinquefolius L.(AGNP),and in vitro antioxidant activities of AGNP were first studied in this work.Methods:AGNP was purified by Ion-exchange chromatography and Gel-filtration chromatography.The chemical characterizations of AGNP were tested by sodium dodecyl sulfate–polyacrylamide gel electrophoresis(SDS-PAGE),high-pressure gel-filtration chromatography,MALDI-TOF-MS and HPLC.In vitro antioxidant effects were tested in simple antioxidant assay including 2,2-diphenylpicrylhydrazyl radical scavenging,superoxide radical(O2^-)scavenging,hydroxyl radical(OH)scavenging,and ferric-reducing ability.Results:The results showed which the content of AGNP measured by Bradford method was 2.42 mg/m L and the subunit molecular weight of AGNP measured by sodium dodecyl sulfate–polyacrylamide gel electrophoresis(SDS-PAGE)was 15 kD.The AGNP molecular weight was 15,114 Da both of SDS-PAGE and mass spectrum purity.The result of high-pressure gel-filtration chromatography demonstrated that the molecular weight of AGNP was 31,086 Da,which implied that AGNP was a homodimer.The in vitro Antioxidant results indicated that AGNP had obvious effects to remove the free radicals in vitro.Conclusion:In conclusion,AGNP had more powerful antioxidant capacity and it can be used as an effective natural antioxidant to alleviate oxidative stress.

Continuous synthesis of iron oxide （Fe3O4） nanoparticles via thermal decomposition

Iron oxide nanoparticles have become of great interest in the medical field for their potential uses in areas such as biomagnetic imaging and hypothermia cancer treatment. Traditionally, particles for these applications are produced through batch-based methodologies. Herein, we demonstrate an alternative continuous flow production method for the synthesis of Fe304 iron oxide nanoparticles. Advantages of continuous flow over the batch method include consistent formation of uniformly spherical particles, thorough mixing of reactants, and capacity for high-volume particle production. In this study, a continu- ous flow reaction mechanism was proposed in which stoichiometric control of reactants had the potential to control final particle size. The project was conducted under the supposition that the iron oleatelligand ratio in the precursor was the greatest size control factor, with a higher ratio resulting in smaller parti- cles. The resulting particles produced by this continuous method were characterized by high-resolution transmission electron microscopy, X-ray diffraction, and magnetometry.

Candidate chiral nuclei in bromine isotopes based on triaxial relativistic mean field theory

Following the observation of candidate chiral doublet bands in ^(78,80)Br, triaxial deformations with corresponding configurations in odd-odd bromine isotopes have been investigated using adiabatic and configuration-fixed constrained triaxial relativistic-meanfield calculations with an aim of finding the boundary of chirality in the chain of Br isotopes. Several minima with triaxial deformation and the proper particle-hole configuration were obtained in ^(74,76,78,80,82)Br, where the chiral doublet bands have the possibility of occurrence. Furthermore, the possible existence of multiple chiral doublet(MχD) bands is demonstrated in ^(74,76,78,80,82)Br.Experiments to explore the chirality and MχD properties of Br isotopes are conducted to verify the predictions.

在水/正辛烷双相体系中利用重组大肠杆菌全细胞合成苯基乳酸的研究（英文）

目的:通过构建水/正辛烷双相体系用于苯基乳酸的合成,有效减轻产物抑制作用,改善细胞活力,增加苯基乳酸的产率及转化率。创新点:在苯基乳酸的全细胞合成中,苯基乳酸的抑制作用导致微生物细胞活力降低,产率较低。本研究旨在降低产物抑制作用来增加苯基乳酸的产率及转化率。方法:从极性不同的几种有机溶剂中筛选能够增加苯基乳酸产量的有机溶剂与水形成双相体系,在水/正辛烷双相体系中利用重组大肠杆菌全细胞转化法合成苯基乳酸,并对该体系转化过程进行优化。部分产物转移至正辛烷相中,减轻了产物抑制作用。结论:本研究通过构建水/正辛烷双相体系全细胞合成苯基乳酸,优化了转化条件。正辛烷相的存在减轻了产物抑制作用。在最佳条件下,双相体系分批补料合成的苯基乳酸明显高于纯水相系统的产量。

Possible candidate nuclei for chirality-parity quartet bands

The potential energy surfaces of the even-even 68-92Se, 112-150Ba, and 208-230Ra isotopes are calculated using the macroscopic-microscopic method in a multidimensional space {αλ,μ} including quadrupole （λ=2, μ=0, 2） and octupole （λ=3, μ=0, 1, 2, 3） degrees of freedom. The calculated results show that the even-even isotopes 92Se, 112,114,144-150Ba and 220-228Ra can exhibit the coexistence of triaxial and octupole deformations, thereby leading to simultaneous chiral and reflected symmetry breaking. Therefore, chirality-parity quartet bands are expected in these and their neighboring odd-A/odd-odd nuclei.

Key factor for determining relation between radius and tidal deformability of neutron stars: Slope of symmetry energy

The constraints on tidal deformability Λ of neutron stars were first extracted from GW170817 by LIGO and Virgo Collaborations.However,the relationship between the radius R and tidal deformability Λ is still under debate.Using an isospin-dependent parameterized equation of state(EOS),we study the relation between R andΛand its dependence on parameters of symmetry energy Esym and EOS of symmetric nuclear matter E0 when the mass is fixed at 1.4 M⊙,1.0 M⊙,and 1.8 M⊙.We find that,although the changes of high order parameters of Esym and E 0 can shift individual values of R1.4 and Λ1.4,the R1.4~Λ1.4 relation remains approximately at the same fitted curve.The slope L of the symmetry energy plays the dominant role in determining the R1.4~Λ1.4 relation.By investigating the mass dependence of the R~Λ relation,we find that the well fitted R~Λ relation for 1.4 M⊙ is broken for massive neutron stars.

Critical point symmetry for odd-odd nuclei and collective multiple chiral doublet bands

A critical point symmetry(CPS) for odd-odd nuclei is built in the core-particle coupling scheme with the even-even core assumed to follow the spherical to triaxially deformed shape phase transition. It is shown that the model Hamiltonian can be approximately solved with the solutions being expressed in terms of the Bessel functions of irrational orders. In particular, the CPS predicts that collective multiple chiral doublets may exist in transitional odd-odd systems.