Probing the peripheral self-generated magnetic field distribution in laser-plasma magnetic reconnection with Martin-Puplett interferometer polarimeter

Magnetic reconnection of the self-generated magnetic fields in laser-plasma interaction is an important laboratory method for modeling high-energy density astronomical and astrophysical phenomena.We use the Martin-Puplett interferometer(MPI)polarimeter to probe the peripheral magnetic fields generated in the common magnetic reconnection configuration,two separated coplanar plane targets,in laser-target interaction.We introduce a new method that can obtain polarization information from the interference pattern instead of the sinusoidal function fitting of the intensity.A bidirectional magnetic field is observed from the side view,which is consistent with the magneto-hydro-dynamical(MHD)simulation results of self-generated magnetic field reconnection.We find that the cancellation of reverse magnetic fields after averaging and integration along the observing direction could reduce the magnetic field strength by one to two orders of magnitude.It indicates that imaging resolution can significantly affect the accuracy of measured magnetic field strength.

Model of self-generated magnetic field generation from relativistic laser interaction with solid targets

Generation of self-generated annular magnetic fields at the rear side of a solid target driven by relativistic laser pulse is investigated by using theoretical analysis and particle-in-cell simulations.The spatial strength distribution of magnetic fields can be accurately predicted by calculating the net flow caused by the superposition of source flow and return flow of hot electrons.The theoretical model established shows good agreement with the simulation results,indicating that the magnetic-field strength scales positively to the temperature of hot electrons.This provides us a way to improve the magnetic-field generation by using a micro-structured plasma grating in front of the solid target.Compared with that for a common flat target,hot electrons can be effectively heated with the well-designed grating size,leading to a stronger magnetic field.The spatial distribution of magnetic fields can be modulated by optimizing the grating period and height as well as the incident angle of the laser pulse.

Two-dimensional investigation of characteristic parameters and their gradients for the self-generated electric and magnetic fields of laser-induced zirconium plasma

Two-dimensional diagnosis of laser-induced zirconium(Zr)plasma has been experimentally performed using the time-of-flight method by employing Faraday cups in addition to electric and magnetic probes.The characteristic parameters of laser-induced Zr plasma have been evaluated as a function of different laser irradiances ranging from 4.5 to 11.7 GW cm-2 at different axial positions of 1–4 cm with a fixed radial distance of 2 cm.A well-supporting correlation between the plume parameters and the laser-plasma-produced spontaneous electric and magnetic(E and B)fields was established.The measurements of the characteristic parameters and spontaneously induced fields were observed to have an increasing trend with the increasing laser irradiance.However,when increasing the spatial distance in both the axial and radial directions,the plasma parameters(electron/ion number density,temperature and kinetic energy)did not show either continuously increasing or decreasing trends due to various kinetic and dynamic processes during the spatial evolution of the plume.However,the E and B fields were observed to be always diffusing away from the target.The radial component of electron number densities remained higher than the axial number density component,whereas the axial ion number density at all laser irradiances and axial distances remained higher than the radial ion number density.The higher axial self-generated electric field(SGEF)values than radial SGEF values are correlated with the effective charge-separation mechanism of electrons and ions.The generation of a self-generated magnetic field is observed dominantly in the radial direction at increasing laser irradiance as compared to the axial one due to the deflection of fast-moving electrons and the persistence of two-electron temperature on the radial axis.

我国慈善超市的定位与发展——与Goodwill的对比分析

Goodwill是世界上最早创立的慈善超市,经过多年发展,已经成为美国最有价值和公认的非营利性品牌之一。反观我国,慈善超市的优势和功能尚未充分显现与发挥,无法实现良性互动。本文通过对比分析我国慈善超市与Goodwill在定位、运作上的差异,思考存在的问题,提出致力于塑造良好的运营氛围,以社区为依托,推动构建就业导向型的新型慈善超市的主张。

Development of self-generated proppant based on modified low-density and low-viscosity epoxy resin and its evaluation

Hydraulic fracturing is a critical technology for the economic development of unconventional oil and gas reservoirs.The main factor influencing fracture propping and reservoir stimulation effect is proppant performance.The increasing depth of fractured oil and gas reservoirs is causing growing difficulty in hydraulic fracturing.Moreover,the migration of conventional proppants within the fracture is always limited due to small fracture width and rigid proppant structure.Thus,proppants with good transportation capacity and fracture propping effects are needed.First,a novel self-generated proppant based on toughened low-viscosity and low-density epoxy resin was developed to satisfy this demand.Then,proppant performances were evaluated.Low-viscosity and low-density epoxy resin was generated when the thiol-ene click chemical reaction product of eugenol and 1-thioglycerol reacts with the epichlorohydrin.Then,the resin was toughened with graphite particles to increase its compressive strength from50.8 to 72.1 MPa based on micro-cracking mechanism and crazing-nail anchor mechanism.The adduct of diethylene triamine and butyl glycidyl ether and the Si O2 nanoparticles were treated as the curing agent and emulsifier respectively to form the emulsion.The emulsion is transformed into solid particles of various sizes within a reservoir to prop the fracture.Evaluation shows good migration capacity of this self-generated proppant due to the low density of epoxy resin.

Business Combinations, Goodwill and Deferred Taxes： Evidences Emerging From a Comparative Analysis Between Italy and Bulgaria

The starting point for the research was the evidence of a possible contradiction in the provisions of IAS 12 on goodwill and deferred income taxes, i.e., about the need to calculate deferred income taxation on temporary differences relating to all assets except for goodwill. This paper aims at exploring the degree of consistency between the theoretical provisions of International Accounting Standards （IAS）/International Financial Reporting Standards （IFRS） and their actual application by the management of Italian and Bulgarian listed companies, as regards the accounting treatments of deferred income taxes relating to the item ＂goodwill＂. The findings suggest that there are some differences between the accounting methods used by the management of most Italian listed companies and the provisions of IAS/IFRS. It can be argued that the rules given by IAS/IFRS are sometimes contradictory, since they may cause doubts in interpretation. As a consequence, in the end of the paper, an amendment to the provisions, set forth in IAS/IFRS concerning the accounting treatment of deferred income taxes relating to the item ＂goodwill＂, is proposed.

Full-Goodwill Method of Accounting for Business Combinations and Quality of Financial Statements

Accounting goodwill arises as a result of business combinations and appears in a consolidated balance sheet of an acquirer. It is an intangible asset which reflects an excess of value of an acquired business as a whole over a summed value of its identifiable net assets. Since 2010, the International Financial Reporting Standards （IFRS） allow for two alternative methods of measuring goodwill in those business combinations, where an acquirer obtains a control over a target company without obtaining 100% share in its shareholder＇s equity. Under one of these methods, which is called a ＂full-goodwill method＂, the goodwill attributable to non-controlling interests in subsidiary is measured at fair value. Thus, the main accounting problem with this method lies in its requirement to estimate the fair value of non-controlling interests. This paper suggests that the ＂full-goodwill method＂ may sacrifice financial statement reliability for its alleged relevance, with significant potential for ＂creative accounting＂. The problems with reliability and transparency of financial statements, when ＂full-goodwill method＂ is applied, are illustrated by a real-life example of the takeover of Formula Systems Ltd. by Asseco Group （one of the biggest IT companies in Europe, listed on the Warsaw Stock Exchange）.

Accounting for goodwill under FRS 136： Case of Malaysian plantation companies

The introduction of FRS （financial reporting standards） 136 to Malaysian PLC＇s （public limited company） in 2006 indirectly formalized accounting for purchased goodwill for the first time. Based on a sample of 2006 annual reports of 10 Main Board companies from plantation sector, the study finds the level of desired disclosure has yet to be met. Whilst the intention of the standard is noble, actual practice for first time reporting entities indicate that Malaysian PLC＇s and their auditors have far to go before they can meet the expectation set by FRS 136 in particular and International Financial Reporting Standards in general.

Disclosure Quality in Goodwill Impairment Tests： Turkey Case

The issue of goodwill impairment has been debated in many countries throughout the world. Adoption of International Financial Reporting Standards （IFRS） introduced fundamental changes in accounting and impairment methods for goodwill. Since global stock markets went into decline in 2008, there has been much debate over the issue of goodwill impairment in the US and European stock exchange markets, especially on how large the write-downs should be. Complexity of International Accounting Standards （IAS） and IFRS focusing on goodwill and goodwill impairment techniques may lead to inconsistent compliance and varying levels of disclosure quality. The aim of this study is to analyze goodwill impairment during and after the recent financial crisis for companies listed on the Borsa Istanbul （BIST） 100 index and to assist the financial statement users in the assessment of disclosure quality under IAS 36, Paragraph 134d. Tools such as： （1） the period over which management has projected cash flows; （2） the growth rate used for cash flow projections; （3） the discount rate（s） applied to projections; and （4） methods employed to determine recoverable amount are analyzed. Insufficient disclosures on these tools are observed. The findings are of interest to researchers examining the implication of IAS 36, regulators, and policy-setters.

Study on the Follow-up Measurement of Goodwill of Listed Companies

Nowadays,the wave of mergers and acquisitions in the capital market is still surging.High evaluation does bring high performance,and the huge impairment of goodwill has become a key factor for the frequent Black Swan events of listed companies.Starting from the essence of goodwill,using Chinese A-share listed companies from 2007 to 2019 as samples and based on the market data,distribution analysis and performance impact,this paper argues that problems of goodwill impairment in China are incomplete accounting standards,inexhaustive impairment implementation and incomprehensive market supervision,thus giving reasonable suggestions.Proper follow-up measurement of goodwill is conducive to improving accounting information quality and adapting to capital market demands,which is of great significance to the revision of international standards.

Study on the Goodwill of Enterprise Merge

The wave of M＆A is generally synchronous with the economic development, the restructuring of society and enterprises, and the enterprises are facing new opportunities and challenges. In the process of business combination, the treatment of goodwill is a special part. There are differences in the treatment of goodwill under the same control of combination and under the different control of combination. Purchase method and equity method are also different. In this paper, the classic case of the merger of China Eastern Airlines and Shanghai Airlines are used to discuss the process of business combination of goodwill and the problems.

Enhancing Understanding,Enlarging Consensus and Depening Friend ship——Highlights of Goodwill Visit to China by the Delegation of World Affairs Council of Jordan

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Farming Change & Goodwill

China’s longest serving political deputy legislator is a witness to history by Guo Ying SHE is an ordinary farmer,who has served a record 57 years in Chinese politics.Born into poverty,she was the first person in China’s history to put forward the concept of "equal pay for equal work" between men and women and as a village cadre she has been received by state leaders on many occasions. Her name is Shen Jilan,Deputy Secretary of the CPC Com-

Development and Performance Evaluation of Self-Generating Enhanced Foam Water Plugging System

For the waterflooding of late development on an offshore oilfield has become worse, and some wells group has entered into high water cut-off period, water plugging work becomes particularly important. Due to the limited construction of offshore oilfield, space water supply difficulties, and stability of plugging agent, self-generating enhanced foam has been designed as the aimed block plugging system. The formula is determined as: 23.25% of NH4Cl + 30% of NaNO2 + 0.1% of catalyst + 0.6% of COSL-3 foaming agent + 0.25% of HS-type HPAM foam stabilizer. Measurement point of pipe with permeability of 0.5 μm2 and 2 μm2 has been used in the plugging and EOR experiments. The experiments show that this system has the selective plugging effect for the heterogeneous formation, especially for middle and posterior part of high permeability formation, and the recovery rate of low permeability pipe is enhanced up to 32.15%.

商誉会计框架体系的经济学范式批判和重构

巨额商誉减值的乱象一直是资本市场的一大顽疾,商誉会计的自省和重塑箭在弦上,刻不容缓。以马克思主义的簿记理论作为评判标准,商誉会计实务表现为“过程的失控”和“观念的偏离”两大职能失位,其背后以自由主义为核心的经济理论范式已不再适用且亟待更新。相较而言,制度主义的诸多观点更符合“商誉”存在的本质要求,依此提出的“预期资产组”或成为商誉会计新框架和体系的突破口。

企业ESG表现与商誉减值

作为重要的非财务信息,企业的ESG表现能否应用于识别商誉减值值得关注。本文以2009—2021年中国A股上市公司为研究对象,考察了企业ESG表现与商誉减值的关系。研究发现:(1)ESG表现越好的企业,商誉减值越少,这意味着企业的ESG表现具有商誉减值识别的作用;(2)良好的ESG表现可以视作企业未来业绩乐观、经营风险较小的积极信号,从而预示着较低的商誉减值;(3)在非国有产权性质、机构持股较少、分析师关注度较低的企业中,企业ESG表现与商誉减值的负向关系更加显著;(4)ESG评级分歧会削弱企业ESG表现与商誉减值间的负向关系。本文基于外部信息使用者视角将企业ESG表现与商誉减值联系起来,为有效识别和防范化解商誉减值风险提供了非财务维度的有益启示。

考虑及时交货和平台商誉的供应链动态决策研究——基于突发事件的视角

供应链在运营过程中不可避免会遭遇突发事件。文章针对发生时间具有随机性,且损害及时交货和平台商誉的突发事件对供应链成员的影响,构建由供应商、平台和零售商组成的三级供应链,探讨了非合作、成本分担和协同合作三种模式下的决策,利用动态微分博弈理论求解不同模式下各成员的最优策略。研究发现:供应商会根据及时交货水平损害率的高低决定突发事件发生后的交货策略,突发事件发生后平台的成本分担行为侧重于扩大市场需求和提升零售商的促销积极性,但对平台商誉水平的提升效果并不明显。协同合作模式下各均衡决策结果均为最优;与非合作模式相比,成本分担模式能够显著提升突发事件发生前后供应商及时交货水平、突发事件发生前平台商誉水平,并实现整体利润的提升。

企业数字化转型与并购商誉泡沫

数字化转型对企业并购的流程和策略产生了深远影响,但能否提升并购质量尚未可知。为此,以2008—2022年沪深A股上市公司为研究样本,从并购商誉泡沫角度入手,分析数字化转型对并购商誉泡沫的影响机理,研究发现企业数字化转型显著促进了并购商誉泡沫,经过一系列稳健性检验后结论依然成立。同时,作用机制检验结果表明,数字化转型会诱发高管过度自信,驱动企业实施溢价并购和激进并购战略,进而促进并购商誉泡沫。进一步分析发现:在民营性质、处于成长期和经过低质量审计这三种情形下,数字化转型对并购商誉泡沫的促进影响更为显著;数字化转型对并购商誉泡沫的推动效应在短期掩盖了抑制效应。研究结论对推动企业“智改数转”、完善数字经济治理体系、促进资本市场健康发展具有重要启示意义。

超额商誉与商业信用成本:基于风险和内控视角

为厘清超额商誉与商业信用成本间的关系,从供应商与企业间融资成本视角出发,以2014—2021年沪深A股公司为样本,基于信号传递理论,分析超额商誉对商业信用成本的影响机制。研究发现:超额商誉正向影响企业商业信用成本;超额商誉通过加剧企业经营风险,进而增加商业信用成本;较高的内部控制质量对超额商誉与商业信用成本间关系起负向调节作用,且随着内部控制质量的提升,超额商誉加剧经营风险的作用会有所减少,相应其对商业信用成本的正向影响也会减弱;在独立董事比例高、高管股权激励水平高和高管薪酬激励水平低的情形下,超额商誉对商业信用成本的正向影响降低,较高的独董比例和高管股权激励能一定程度缓解超额商誉的负面影响。

科学研究中的“善意”监督及其路径探究

科学共同体内部的监督对披露科研不端行为、加强学风建设有重要作用,但应在“善意”这一基本原则指导下进行。“善意”监督往往会因为主观偏见盛行和客观保障缺失而陷入困境。为实现“善意”监督,应通过科研伦理教育进行主观引导,并通过完善相关科研伦理规范、规范监督和举报程序、健全奖惩制度、建立救济制度等措施为“善意”监督提供客观保障。