New Insights into the Essential Reason of Liquid Foundation Darkening from the Powder Point of View

Perfect base makeup is the guarantee of exquisite makeup.However,the problem of base makeup darkening seriously affects the cosmetic effect,and also troubles many researchers and consumers.In this paper,a basic liquid foundation was chosen as model to explore the darkness reason from the aspects of foundation hue,volatility of emulsification system,and sebum secretion.DEcmc value determined by non-contact colorimeter was used to monitor the process of darkness.It’s widely accepted that foundation oxidation is key to darkness.We herein report a new insight into the essential reason of darkness due to the interaction between light and foundation.The red hue of the foundation darkened faster because the human eyes were more sensitive to the color difference of red.The volatility of foundation emulsion system and skin sebum secretion accelerated the foundation darkening process,which was caused by the change of foundation surface structure.Considering the above influencing factors,the formula was adjusted and an improved formula was proposed,which could significantly reduce the process of foundation darkening.

PLD Preparation of GeS_6 Amorphous Film and Investigation on Its Photo-induced Darkening Phenomenon

GeS6 chalcogenide amorphous fi lm was deposited on glass substrate via PLD（pulsed laser deposition） technique. The performance and structure of the fi lm was characterized by XRD（X-ray diffraction）, SEM（Scanning Electron Microscopy）, EDS（Energy Dispersive Spectroscopy）, optical transmission spectra, and Raman spectra, etc. The GeS6 amorphous fi lm was irradiated by 532 nm linearly polarized light, and its photoinduced darkening was investigated. The results showed that the GeS6 chalcogenide amorphous fi lm was smooth and compact with uniform thickness and combined with the substrate fi rmly, and its chemical composition was in consistency with the bulky target. When laser energy was fi xed, the transparence of the fi lm declined with the increase of the laser irradiation time. Obvious photo-induced darkening and relaxation phenomenon of the fi lm after laser irradiation were observed in this investigation.

Study on the Factors Affecting the Darkening of Liquid Foundations

To explore the factors affecting the darkening of liquid foundations,the liquid foundations containing differently treated titanium dioxide and different types of filling powders were studied from three aspects,including sebum,sweat and light.The darkening factors of liquid foundations were analyzed by comparing the luminance difference using color spectrophotometer.The results showed that sebum is the main cause of the darkening effect,and the impact of sweat and light are less.

Impacts of land surface darkening on frozen ground and ecosystems over the Tibetan Plateau

Tibetan Plateau(TP) is known as the “Third Pole” of the Earth. Any changes in land surface processes on the TP can have an unneglectable impact on regional and global climate. With the warming and wetting climate, the land surface of the TP saw a darkening trend featured by decreasing surface albedo over the past decades, primarily due to the melting of glaciers, snow,and greening vegetation. Recent studies have investigated the effects of the TP land surface darkening on the field of climate, but these assessments only address one aspect of the feedback loop. How do these darkening-induced climate changes affect the frozen ground and ecosystems on the TP? In this study, we investigated the impact of TP land surface darkening on regional frozen ground and ecosystems using the state-of-the-art land surface model ORCHIDEE-MICT. Our model results show that darkening-induced climate changes on the TP will lead to a reduction in the area of regional frozen ground by 1.1×10~4±0.019×10~4km~2, a deepening of the regional permafrost active layer by 0.06±0.0004 m, and a decrease in the maximum freezing depth of regional seasonal frozen ground by 0.06±0.0016 m compared to the scenario without TP land surface darkening.Furthermore, the darkening-induced climate change on the TP will result in an increase in the regional leaf area index and an enhancement in the regional gross primary productivity, ultimately leading to an increase in regional terrestrial carbon stock by0.81±0.001 PgC. This study addresses the remaining piece of the puzzle in the feedback loop of TP land surface darkening, and improves our understanding of interactions across multiple spheres on the TP. The exacerbated regional permafrost degradation and increasing regional terrestrial carbon stock induced by TP land surface darkening should be considered in the development of national ecological security barrier.

Radiation dimming and decreasing water clarity fuel underwater darkening in lakes

Long-term decreases in the incident total radiation and water clarity might substantially affect the underwater light environment in aquatic ecosystems.However,the underlying mechanism and relative contributions of radiation dimming and decreasing water clarity to the underwater light environment on a national or global scale remains largely unknown.Here,we present a comprehensive dataset of unprecedented scale in China’s lakes to address the combined effects of radiation dimming and decreasing water clarity on underwater darkening.Long-term total radiation and sunshine duration showed 5.8%and 7.9%decreases,respectively,after 2000 compared to 1961–1970,resulting in net radiation dimming.An in situ Secchi disk depth(SDD)dataset in 170 lakes showed that the mean SDD significantly decreased from 1.80±2.19 m before 1995 to 1.28±1.82 m after 2005.SDD remote sensing estimations for 641 lakes with areas≥10 km^2 showed that SDD markedly decreased from 1.26±0.62 m during 1985–1990 to 1.14±0.66 m during 2005–2010.Radiation dimming and decreasing water clarity jointly caused an approximately 10%decrease in the average available photosynthetically active radiation(PAR)in the euphotic layer.Our results revealed a more important role of decreasing water clarity in underwater darkening than radiation dimming.A meta-analysis of long-term SDD observation data from 61 various waters further elucidated a global extensive underwater darkening.Underwater darkening implies a decrease in water quality for potable water supplies,recession in macrophytes and benthic algae,and decreases in benthic primary production,fishery production,and biodiversity.

Unprecedented snow darkening and melting in New Zealand due to 2019–2020 Australian wildfires

Wildfire events have recently shown a rapid increase in frequency and scale due to the warmer present-day climate;however,their potential effects on the cryosphere are difficult to assess.Catastrophic wildfires in Australia during 2019–2020 emitted large amounts of light-absorbing particles(LAPs)to the atmosphere.Satellite observations indicate that these LAPs caused unprecedented snow-darkening of glaciers in New Zealand through long-range transport and deposition,with their effects lasting for up to three months in January–March 2020,influencing>90%of total glacier/snow and leading to a mean broadband snow-reflectance reduction of 0.08±0.03.This snow darkening accelerated snowmelt by~0.41±0.2 cm day–1 during the southern summer,equivalent to that caused by a~1.8°C increase in air temperature.This indicates the significant impact of the 2019–2020 Australian wildfires on the hydrologic cycle in New Zealand,exceeding that of the local climate warming of~1.5°C since the preindustrial period.Wildfire-induced snow darkening is not limited to New Zealand.Future projections of wildfire incidence indicate widespread effects of snow darkening on the global cryosphere.

高掺杂浓度掺镱光纤的光子暗化效应

采用光纤激光器和放大器结构方案,观察到了高浓度掺镱光纤(YDF)的光子暗化(Photo-darkening)现象.对激光器阈值和输出功率、放大器输出谱的测量结果表明,光子暗化效应导致了高掺杂浓度YDF的功率转换效率随泵浦作用时间的增加而下降,且下降为单调不可逆过程,但随着泵浦时间的增加,这种下降逐渐变缓、功率转换效率最终可趋于稳定.

Kirkendall效应和空心纳米晶体的人工合成

在1946年被发现的Kirkendall效应,对科学技术引起很大的冲击,至今,仍在许多科学技术和工程领域受到关注。本文悦目瞭然地阐述Kirkendall效应和Darken分析,计算实例,空位风和反Kirkendall效应。最后,更为重要地指明,2004年发表的应用纳米尺度Kirkendall效应人工合成中空纳米球方法提供了人工合成无机化合物的空心纳米晶体和纳米管的通用途径。近年来,这种具有空心结构的纳米晶体愈来愈受到人们的青睐。

钯–硅(Pd-Si)薄膜表面偏析研究

本文应用修正的Darken模型,结合考虑薄膜尺寸效应的约束条件,对PdSi、Pd2Si、Pd3Si、Pd9Si2、Pd5Si合金薄膜的平衡态及动态表面偏析进行了模拟计算,其中,偏析参数,即偏析能ΔG和相互作用系数Ω,分别由Miedema模型和相图计算方法获得。结果表明:尺寸效应对Pd-Si合金薄膜体系偏析的影响不是很明显。

二元Pd-X与三元Pd-X-PdO (X = Ag, Au, Cu, Ni, Pt)合金表面偏析的研究

本文利用修正的Darken模型研究了二元Pd-X和三元Pd-X-PdO (X = Ag, Au, Cu, Ni, Pt)合金平衡及动态的表面偏析,利用Miedema模型计算了合金体系的偏析能和相互作用系数。通过模拟氧化物PdO与合金元素表面偏析的竞争,预测了氧化物PdO对Pd-X合金表面偏析的影响。这些结果为研究由偏析引起Pd基合金表面成分的变化提供了指导。

Influence of Electric Current on Kirkendall Diffusion of Zn/Cu Couples

The influence of electric current on Kirkendall diffusion in Zn/Cu couples was investigated. Under the action of different electric currents, the Zn/Cu diffusion couples were annealed at 785℃ for different holding time. The experimental results show that the displacement of the Kirkendall plane increases with increasing holding time. However, the displacement of the Kirkendall plane with electric current is larger than that without electric current. The relationship between the displacement of the Kirkendall plane and the holding time is changed under the action of electric current. The likely reason for the electric current enhancing effect is the energy transfer from electron to jumping atom, increasing the integrated diffusion coefficient, which leads to the increase in the velocity of Kirkendall plane.

A Mathematical Model and Simulations of Low Temperature Nitriding Katarzyna Tkacz-Smiech Deceased.We dedicate this article to the memory of Professor Katarzyna Tkacz-Smiech

Low-temperature nitriding of steel or iron can produce an expanded austenite phase,which is a solid solution of a large amount of nitrogen dissolved interstitially in fcc lattice.It is characteristic that the nitogen depth profiles in expanded austenite exhibit plateau-type shapes.Such behavior cannot be considered with a standard analytic solution for diffusion in a semi-infinite solid and a new approach is necessary.We formulate a model of interdiffusion in viscoelastic solid(Maxwellmodel)during the nitriding process.It combines themass conservation and Vegard’s rule with the Darken bi-velocity method.The model is formulated in any dimension,i.e.,a mixture is included in R^(n),n=1,2,3.For the system in one dimension,n=1,we transform a differential-algebraic system of 5 equations to a differential system of 2 equations only,which is better to study numerically and analytically.Such modification allows the formulation of effective mixed-type boundary conditions.The resulting nonlinear strongly coupled parabolic-elliptic differential initial-boundary Stefan type problem is solved numerically and a series of simulations is made.

Ending of Darken Equation and Intrinsic Diffusion Concept

The well-known Darken equation has been widely accepted in analyzing interdiffusion problems since 1948. The diffusion researchers have never conceived a doubt about the validity of Darken equation for such a long time. However, it is revealed that the Darken equation is inconsistent with the fundamental theory in mathematics. At the same time, it is clarified that the well-known intrinsic diffusion concept is an illusion. The present brief report will have a great influence on matters of the research and education relevant to diffusion problems not only in future but also in past, since the accumulated diffusivity data analyzed by the invalid Darken theory and the misjudged descriptions in existing text books should be revised or deleted as soon as possible.

青藏高原地表变暗与北极气候变化间的共振

The Tibetan Plateau(TP)exerts a profound influence on global climate over million-year timescales due to its past uplift.However,whether the ongoing climate changes over the TP,particularly the persistent reduction in its local albedo(referred to as“TP surface darkening”),can exert global impacts remains elusive.In this study,a state-of-the-art coupled land–atmosphere global climate model has been employed to scrutinize the impact of TP darkening on polar climate changes.Results indicate that the projected TP darkening has the potential to generate a stationary Rossby wave train,thereby modulating the atmospheric circulation in the high-latitudes of the Northern Hemisphere and instigating a dipole-like surface air temperature anomaly pattern around the Arctic region.An additional experiment suggests that the projected Arctic warming may in return warm the TP,thus forming a bi-directional linkage between these two climate systems.Given their association with vast ice reservoirs,the elucidation of this mechanism in our study is crucial in advancing our comprehension of Earth system climate projections.

Broadband photochromic effect and photoluminescence modulation in rare-earth-doped(Pb,La)(Zr,Ti)O3 ceramics

The broadband photochromic effect on undoped and rare-earth-doped lead lanthanum zirconate titanate(PLZT) ceramics was studied under the illumination of ultraviolet light at 360 nm. The photocarriers’ trapping and detrapping processes of thermal disconnected traps played the vital role in both darkening and bleaching processes. The interaction between photocarrier traps and rare-earth ion energy levels was demonstrated, which influenced the photochromatic darkening performance greatly. The transformation of photoluminescence spectra in Er3+-doped PLZT ceramics also improved the physical picture of the trap’s distribution of the materials.This work could be used to modulate the photoluminescence and lasing behavior.