专栏导语:中国场景下的治理逻辑

自“治理”成为一个学术性概念,进而演化为一个专门的理论和实践模式以来,研究者对其所作的阐释是多元化的。就其基本的指向而言,它与传统的官僚制行政模式和市场制行政模式不同,意味着持续而稳定的多元化力量共同致力于现代社会中复杂问题的有效解决。在中国语境下,究竟何谓治理?治理的价值和功能有何特殊之处?治理的基础和基本逻辑又是什么?这需要在中国场景下予以更多的讨论和检视,为治理研究的学术共同体作出更多的贡献。在中国的经济和社会发展中,寻求有效的管理模式来应对多元化的目标、任务和挑战,是治理研究的重要使命。治理的一系列主张具有高度的整合性,在实际的运转中对条件的要求也更加苛刻。关键的是,我们需要发现和塑造治理的机制,以更好地使其成为求解“糟糕型”公共事务问题的一剂良方。就此而言,中国意义上的“组合拳”与“复合化”也许是在中国场景下透视治理的最为重要关键词。

Rational Design of Layered SnS2 on Ultralight Graphene Fiber Fabrics as Binder-Free Anodes for Enhanced Practical Capacity of Sodium-Ion Batteries

Generally,the practical capacity of an electrode should include the weight of non-active components such as current collector,polymer binder,and conductive additives,which were as high as 70 wt%in current reported works,seriously limiting the practical capacity.This work pioneered the usage of ultralight reduced graphene fiber(rGF)fabrics as conductive scaffolds,aiming to reduce the weight of nonactive components and enhance the practical capacity.Ultrathin SnS2 nanosheets/rGF hybrids were prepared and used as binder-free electrodes of sodium-ion batteries(SIBs).The interfused graphene fibers endow the electrode a porous,continuous,and conductive network.The in situ phase transformation from SnO2 to SnS2 could preserve the strong interfacial interactions between SnS2 and graphene.Benefitting from these,the designed binder-free electrode delivers a high specific capacity of 500 mAh g?1 after 500 cycles at a current rate of 0.5 A g?1 with almost 100%Coulombic efficiency.Furthermore,the weight percentage of SnS2 in the whole electrode could reach up to 67.2 wt%,much higher than that of common electrode configurations using Cu foil,Al foil,or carbon cloth,significantly highlighting the ultralight characters and advantages of the rGF fabrics for using as binder-free electrodes of SIBs.

固态锂金属电池用无枝晶锂负极的通用亲锂界面层的构建

固态锂金属电池具有高安全性和高能量密度的优势,被认为是最有前景的下一代电池体系.石榴石型固体电解质(LLZO)具有较高的离子电导率、良好的机械性能和对锂金属稳定等优点,成为当前的研究焦点.然而,固态电解质与金属锂之间较差的固固界面接触和界面处不均匀的锂沉积严重阻碍了固态电池的实际应用.本文提出一种改善固态电解质/锂负极界面润湿性的通用方法,通过在固态电解质表面滴加一层亲锂的氧化钴量子点,原位构建Co/Li_(2)O中间层.该方法不仅可以显著降低固态电解质与金属锂之间的界面阻抗,还可以调节界面处锂离子均匀沉积,有效抑制锂枝晶的生长.得益于原位构建的亲锂和导锂离子的Co/Li_(2)O中间层,当组装成锂对称电池时,其可在0.3 m A cm^(-2)的电流密度下稳定循环1696 h,且循环时过电位没有明显变化.匹配正极Li Fe PO_(4)(LFP)或Li_(1.4)Mn_(0.6)Ni_(0.2)Co_(0.2)O_(2.4)(LMNC622)的固态电池在25℃下能够稳定循环,且具有较高的放电比容量和库伦效率.

An Anti-Recompression Video Watermarking Algorithm in Bitstream Domain

Following the popularity of digital video application,video copying and dissemination have become very easy;however,this makes video hacking and piracy a potential threat in video communication.Video watermarking technology can solve the problem of copyright protection,and thus,it has been extensively researched.The robustness of the video watermarking algorithm in the bitstream domain is poor,especially the anti-recompression ability,since the watermarked video may be compressed again before transmitting.Considering this,this paper proposes a video watermarking algorithm in the bitstream domain based on moving object detection.To increase the robustness of the watermarking scheme,the moving macroblocks that belong to the moving object in each P frame can be identified via the moving object detection algorithm.Then,watermark embedding in the moving macroblocks is performed using codeword substitution to ensure the consistency of the bitstream.Moving object detection and watermark embedding are independent and are both carried out in the bitstream domain by partially decoding the bitstream;this avoids the complete decoding and reconstruction of the video,making the method to be highly efficient.The simulation results confirm that the proposed method is robust against recompression and has little impact on the video visual quality and no influence on the bit rate.

High throughput materials research and development for lithium ion batteries

Development of next generation batteries requires a breakthrough in materials.Traditional one-by-one method,which is suitable for synthesizing large number of sing-composition material,is timeconsuming and costly.High throughput and combinatorial experimentation,is an effective method to synthesize and characterize huge amount of materials over a broader compositional region in a short time,which enables to greatly speed up the discovery and optimization of materials with lower cost.In this work,high throughput and combinatorial materials synthesis technologies for lithium ion battery research are discussed,and our efforts on developing such instrumentations are introduced.

Fabrication of high Li:water molar ratio electrolytes for lithium-ion batteries

Hydrous electrolytes with high electrochemical potentials were obtained by hydrating water molecules into solutes to form high Li:water molar ratio electrolytes(HMRE).Solid polyethylene glycol(PEG) were e mployed to enha nce the molar ratio of Li^(+) to water in the electrolytes while reducing the consumption of Li-salt.The obtained mole ratio of Li^(+) to wa ter molecules in the hydrous electrolytes was greater than 1:1;however,the mass fraction of Li-salt was reduced to 61%(approximately 5.5 mol/kg,based on water and PEG).Compared with that of water-in-salt electrolytes,the mass fraction of Li-salt could be remarkably reduced by adding solid PEG.The electrochemical stability of the electrolytes improved considerably because of the strong hydration of Li^(+) by the water molecules.A beneficial passivation effect,arising from the decomposition of the electrolyte,at a wide potential window was observed.

DIP-MOEA:a double-grid interactive preference based multi-ob jective evolutionary algorithm for formalizing preferences of decision makers

The final solution set given by almost all existing preference-based multi-objective evolutionary algorithms(MOEAs)lies a certain distance away from the decision makers’preference information region.Therefore,we propose a multi-ob jective optimization algorithm,referred to as the double-grid interactive preference based MOEA(DIPMOEA),which explicitly takes the preferences of decision makers(DMs)into account.First,according to the optimization ob jective of the practical multi-ob jective optimization problems and the preferences of DMs,the membership functions are mapped to generate a decision preference grid and a preference error grid.Then,we put forward two dominant modes of population,preference degree dominance and preference error dominance,and use this advantageous scheme to update the population in these two grids.Finally,the populations in these two grids are combined with the DMs’preference interaction information,and the preference multi-ob jective optimization interaction is performed.To verify the performance of DIP-MOEA,we test it on two kinds of problems,i.e.,the basic DTLZ series functions and the multi-ob jective knapsack problems,and compare it with several different popular preference-based MOEAs.Experimental results show that DIP-MOEA expresses the preference information of DMs well and provides a solution set that meets the preferences of DMs,quickly provides the test results,and has better performance in the distribution of the Pareto front solution set.

Single-shot three-input phase retrieval for quantitative back focal plane measurement

This paper presents quantitative measurements facilitated with a new optical system that implements a single-shot three-input phase retrieval algorithm. The new system allows simultaneous acquisition of three distinct input patterns, thus eliminating the requirement for mechanical movement and reducing any registration errors and microphonics. We demonstrate the application of the system for measurement and separation of two distinct attenuation measurements of surface waves, namely, absorption and coupling loss. This is achieved by retrieving the phase in the back focal plane and performing a series of virtual optics computations. This overcomes the need to use a complicated series of hardware manipulations with a spatial light modulator. This gives a far more accurate and faster measurement with a simpler optical system. We also demonstrate that phase measurements allow us to implement different measurement methods to acquire the excitation angle for surface plasmons. Depending on the noise statistics different methods have superior performance, so the best method under particular conditions can be selected. Since the measurements are only weakly correlated, they may also be combined for improved noise performance. The results presented here offer a template for a wider class of measurements in the back focal plane including ellipsometry.

Preparation of safe water-lipid mixed electrolytes for application in ion capacitor

Aqueous electrolytes are safe,economic,and environmentally friendly.However,they have a narrow potential window.On the other hand,organic electrolytes exhibit good thermodynamic stability but are inflammable and moisture sensitive.In this study,we prepared water-PEG-lipid ternary electrolytes(TEs).To combine the advantages of water,polyethylene glycol(PEG)and propylene carbonate(PC).The nonflammable mixed electrolytes exhibited a wide potential window of about 2.8 V due to the beneficial effects of PEG and PC.Using these TEs,a lithium manganate-active carbon ion capacitor could be operated at 2.4 V with an energy density of 32 Wh/kg,based on the total active electrode material(current density of 3.3 m A/cm^(2)).This value was significantly higher than that achieved using an aqueous electrolyte,thereby rationalizing the higher energy density.

Frontier luminous strategy of functional silica nanohybrids in sensing and bioimaging:From ACQ to AIE

Fluorescent silica organic-inorganic nanohybrids which combine designable luminescence performance of organic fluorescent dyes and various outstanding advantages of silica nanomaterials have attracted increasing research interests in these fascinating areas.Optical transparency and facile functional modification properties of silica material provide great opportunities to integrate desired fluorescent molecules for various frontier luminous applications.However,conventional organic dyes are typically subject to aggregation-caused quenching due to their aggregation in silica matrix,which could be detrimental for their performance in sensing and biomedical applications.The appearance of aggregation-induced emission luminogens(AIEgens)paves a new way for developing highly efficient fluorescent silica nanohybrids(FSNs).FSNs with intensive luminescence could be obtained due to the formation of aggregates and the restricted intramolecular motion of AIEgens in silica inorganic matrix.In this review,the reported fabrication methodologies of various FSNs based on colloidal silica nanoparticles(SNs)and mesoporous SNs including physical entrapment and covalent strategies are summarized.Especially,the AIEgens-functionalized silica hybrid nanomaterials are introduced in detail.Furthermore,chemical sensing,biosensing,and bioimaging applications of resultant FSNs are also discussed.