Seasonal influence of freshwater discharge on spatio-temporal variations in primary productivity, sea surface temperature, and euphotic zone depth in the northern Bay of Bengal

Ocean productivity is the foundation of marine food web,which continuously removes atmospheric carbon dioxide and supports life at sea and on land.Spatio-temporal variability of net primary productivity(NPP),sea surface temperature(SST),sea surface salinity(SSS),mixed layer depth(MLD),and euphotic zone depth(EZD) in the northern B ay of Bengal(BoB) during three monsoon seasons were examined in this study based on remote sensing data for the period 2005 to 2020.To compare the NPP distribution between the coastal zones and open BoB,the study area was divided into five zones(Z1-Z5).Results suggest that most productive zones Z2 and Zl are located at the head bay area and are directly influenced by freshwater discharge together with riverine sediment and nutrient loads.Across Z1-Z5,the NPP ranges from 5 315.38 mg/(m^(2)·d) to 346.7 mg/(m^(2)·d)(carbon,since then the same).The highest monthly average NPP of 5 315.38 mg/(m^(2)·d) in February and 5 039.36 mg/(m^(2)·d) in June were observed from Z2,while the lowest monthly average of 346.72 mg/(m^(2)·d) was observed in March from Z4,which is an oceanic zone.EZD values vary from 6-154 m for the study area,and it has an inverse correlation with NPP concentration.EZD is deeper during the summer season and shallower during the wintertime,with a corresponding increase in productivity.Throughout the year,monthly SST shows slight fluctuation for the entire study area,and statistical analysis shows a significant correlation among NPP,and EZD,overall positive between NPP and MLD,whereas no significant correlation among SSS,and SST for the northern BoB.Long-term trends in SST and productivity were significantly po sitive in head bay zones but negatively productive in the open ocean.The findings in this study on the distribution of NPP,SST,SSS,MLD,and EZD and their seasonal variability in five different zones of BoB can be used to further improve the management of marine resources and overall environmental condition in response to climate changes in BoB as they are of utmost relevance to the fisheries for the three bordering countries.

The Formation of Colored Film on Stainless Steel and the Study for Surface Structure

This paper discusses the coloration process on the stainless steel and the properties of the film. The compositions, morphology and structure of colored films on stainless steel are studied by using SEM,AES,AFM,STM. The diffusion controlled mechanisms of films and calculation formula of surface electropotential difference are discussed.

Generating micro/nanostructures on magnesium alloy surface using ultraprecision diamond surface texturing process

The lightness and high strength-to-weight ratio of the magnesium alloy have attracted more interest in various applications.However,micro/nanostructure generation on their surfaces remains a challenge due to the flammability and ignition.Motivated by this,this study proposed a machining process,named the ultraprecision diamond surface texturing process,to machine the micro/nanostructures on magnesium alloy surfaces.Experimental results showed the various microstructures and sawtooth-shaped nanostructures were successfully generated on the AZ31B magnesium alloy surfaces,demonstrating the effectiveness of this proposed machining process.Furthermore,sawtooth-shaped nanostructures had the function of inducing the optical effect and generating different colors on workpiece surfaces.The colorful letter and colorful flower image were clearly viewed on magnesium alloy surfaces.The corresponding cutting force,chip morphology,and tool wear were systematically investigated to understand the machining mechanism of micro/nanostructures on magnesium alloy surfaces.The proposed machining process can further improve the performances of the magnesium alloy and extend its functions to other fields,such as optics.

Surface photometry and radial color gradients of nearby luminous early-type galaxies in SDSS Stripe 82

We make use of the images from the Sloan Digital Sky Survey Stripe 82（Stripe 82） to present an analysis of r band surface brightness profiles and radial color gradients（g-r,u-r） in our sample of 111 nearby early-type galaxies（ETGs） .Thanks to the Stripe 82 images,each of which is co-added from about 50 single frames,we are able to pay special attention to the low-surface-brightness areas（LSB areas） of the galaxies.The LSB areas affect the Sérsic fittings and concentration indices by making both of the indices less than the typical values for ETGs.In the Sérsic fits to all the surface brightness profiles,we found some Sérsic indices that range from 1.5 to 2.5,much smaller than those of typical de Vaucouleur profiles and relatively close to those of exponential disks,and some others much larger than four but still with accurate fitting.Two galaxies cannot be fitted with a single Sérsic profile,but once we try double Sérsic profiles,the fittings are improved：one with a profile relatively close to the de Vaucouleur law in the inner area and a profile relatively close to an exponential law in the LSB area,the other with a nice fitting in the inner area but still having a failed fitting in the outer area.About 60%of the sample has negative color gradients（red-core） within 1.5Re,much more than the approximately 10%positive ones（blue-core） within the same radius.However,taking into account the LSB areas,we find that the color gradients are not necessarily monotonic：about one third of the red-core（or blue-core） galaxies have positive（or negative） color gradients in the outer areas. So LSB areas not only make ETGs’Sérsic profiles deviate from de Vaucouleur ones and shift to the disk end,but also reveal that quite a number of ETGs have opposite color gradients in inner and outer areas.These outcomes remind us of the necessity of double-Sérsic fitting.These LSB phenomena may be interpreted by mergers and thus have different metallicity in the outer areas.Isophotal parameters are also discussed briefly in this paper with the following conclusion：there are more disky nearby ETGs that are identified than boxy ones.

THE EFFECT OF WOOD SURFACE ROUGHNESS OF DIFFERENT SPECIES OF TREES ON WOOD COLOR IN WORKING OPERATION

The multinomial wood surface roughness parameters and wood color parameters of 5 kinds of species of trees were measured in working operation by the stylus surface roughness meter and colorimeter, and the measurement results were compared. The results indicated: The variations of wood surface roughness had the effect on the wood color of some kinds of species of trees on working operation, with the surface roughness decreasing, the brightness and luminance exponent increased, the hue angle increased lightly, but the variation of color saturation was different to the different wood color hue of species of trees.

Design and fabrication of structural color by local surface plasmonic meta-molecules

In this paper, we propose a new form of nanostructures with Al film deposited on a patterned dielectric material for generating structural color, which is induced by local surface plasmonic resonant(LSPR) absorption in sub-wavelengthindented hole/ring arrays. Unlike other reported results obtained by using focus ion beam(FIB) to create metallic nanostructures, the nano-sized hole/ring arrays in Al film in this work are replicated by high resolution electron beam lithography(EBL) combined with self-aligned metallization. Clear structural color is observed and systematically studied by numerical simulations as well as optical characterizations. The central color is strongly related to the geometric size, which provides us with good opportunities to dye the colorless Al surface by controlling the hole/ring dimensions(both diameter and radius), and to open up broad applications in display, jewelry decoration, green production of packing papers, security code,and counterfeits prevention.

The Effects of Porcelain Polishing Techniques on the Color and Surface Texture of Different Porcelain Systems

The aim of this study was to compare the effects of different porcelain polishing techniques on the color change and surface roughness of feldspathic porcelains and lithium disilicate glass-ceramic system. 80 porcelain specimens were divided into two subgroups, each subgroup was divided into 4 groups of 10 specimens. Surfaces were polished with different ceramic polishers. VITA Easyshade spectrophotometer was used to measure color differences. Surface roughness was evaluated using a profilometer. The color change and surface roughness of porcelains were statistically analyzed by Two-way ANOVA followed by a Tukey HSD test (α = 05). There were relationships between the porcelain systems and polishing techniques (p 0.05). For △E values, there was relationship between the porcelain systems and polishing techniques (p 0.05). Chairside porcelain polishing systems were not able to provide a porcelain surface as smooth as the glazed surface for the IPS empress and Ceramco 3 porcelains.

Large-area straight,regular periodic surface structures produced on fused silica by the interference of two femtosecond laser beams through cylindrical lens

Inhomogeneity and low efficiency are two important factors that limit the application of laser-induced periodic surface structures(LIPSSs),especially on glass surfaces.In this study,two-beam interference(TBI)of femtosecond lasers was used to produce large-area straight LIPSSs on fused silica using cylindrical lenses.Compared with those produced us-ing a single circular or cylindrical lens,the LIPSSs produced by TBI are much straighter and more regular.Depending on the laser fluence and scanning velocity,LIPSSs with grating-like or spaced LIPSSs are produced on the fused silica sur-face.Their structural colors are blue,green,and red,and only green and red,respectively.Grating-like LIPSS patterns oriented in different directions are obtained and exhibit bright and vivid colors,indicating potential applications in surface coloring and anti-counterfeiting logos.

Ocular surface heat effects on ocular hemodynamics detected by real-time measuring device

AIM: To investigate the ocular hemodynamic effects of applying a hot compress to the eye.METHODS: The right eyes of five New Zealand white rabbits, both male and female, were hot-compressed for 18 min. An independently designed novel ocular contacttype temperature measuring device was used to measure the ocular surface temperature before and after the heating. Relevant retrobulbar hemodynamic parameters such as peak systolic velocity(PSV), end diastolic velocity(EDV), and resistance index(RI) of each of the central retinal artery(CRA), long posterior ciliary artery(LPCA), and ophthalmic artery(OA), as well as the mean velocity(V_m) of the central retinal vein(CRV), were measured using a color Doppler flow imaging(CDFI) technique and expressed as mean values with standard deviation(mean±SD). A statistical analysis was conducted based on a paired t-test and the Wilcoxon signed-rank test. RESULTS: The employed real-time temperature measuring device was able to accurately measure ocular surface temperature during the hot-compress process. The temperature increased after the hot compress was applied. Analysis showed that the PSV and EDV values of the CRA and LPCA significantly increased after the application of the hot compress, as did the V_m of the CRV. There were no significant changes in the EDV of the OA nor the RI of each artery. CONCLUSION: This experiment, which is the first of its kind, confirms that the retrobulbar blood flow velocities can increase upon heating the ocular surface. This simple method may be useful in the future.

Relationship between Lingual Papilla Surface Roughness and Oral Condition in Elderly Individuals

Objectives: Recently, an increasing number of elderly patients have complained of tongue pain and fissured tongue, while atrophy of the lingual papillae with low nutrition has also become a commonly encountered condition. The viewpoint that lingual papilla atrophy reflects systemic and pathological conditions, such as diabetes and in the circulatory system abnormalities, is supported by many clinicians. The present study was conducted to clarify the relationship of degree of atrophy of tongue papillae with oral symptoms, with an aim to evaluate the usefulness of clinical diagnostic criteria for tongue papillae atrophy. Subjects and Methods: The subjects were asked to protrude the tongue forward. The tongue was held at rest and impressions were taken of the tongue dorsum 15 mm posterior to the apex of the tongue. Surface impressions were measured using a Surfcoder SE300 and the obtained values were used to define surface roughness (Ra). Multivariate analyses of the relationships between the Ra measurements and the living environment, subjective symptoms of oral health, and survey results of measurements were performed to examine factors associated with Ra. The tongue was photographed with a digital camera, then RGB color value of four random points 15 mm from the tongue apex was determined. Using those findings, redness was calculated. Results and Conclusions: One hundred and six subjects with a mean age of 79.5 ± 9.2 years were analyzed. In the smooth group, there was more redness in the tongue dorsum as compared to the rough group. Total and Sagittal Ra values of subjects with dysphagia were lower than those without dysphagia, suggesting that the degree of oral mucosal atrophy is related to subjective symptoms of dysphagia. Subjects with high water intake had higher Coronal Ra values, which was considered to be related to the edematous state of the lingual papillae.

冷轧板边部表面色差缺陷原因分析及改进措施

针对生产st13镀锌用冷轧板边部表面色差缺陷问题,对热轧板和酸洗板表面粗糙度进行了检测分析,结果表明,热轧板边部与中间部位的表面粗糙度差异大是边部表面产生色差的主要原因。结合热轧板横断面的铁皮厚度,分析了钢板表面粗糙度差异大的原因。根据实际生产情况,调整冷轧末机架轧机负荷和优化板形,改善钢板表面的色差缺陷,通过合理匹配热轧卷取温度和层流冷却模式,解决了st13钢板表面的边部色差问题。

基于鲜切苹果保鲜的可食性复合保鲜膜配方优化

以海藻酸钠、羧甲基纤维素钠、壳聚糖为主要原料制备可食性复合保鲜膜。由单因素实验制得复合膜,根据复合膜的性能及其对鲜切苹果的保鲜效果获得最优的单因素。在此基础上,应用响应面法优化复合膜的工艺组合并验证其保鲜效果。结果表明,经响应面法优化后的复合膜主要原料配方为:壳聚糖添加量0.98 g,海藻酸钠添加量1.55 g,羧甲基纤维素钠添加量1.31 g。应用该复合保鲜膜进行鲜切苹果保鲜,得到处理样品的色差a值5.95、DPPH自由基清除率35.27%、ABTS自由基清除率34.43%,而对照样品的a值9.10、DPPH自由基清除率21.31%、ABTS自由基清除率27.62%。该可食性复合保鲜膜具有良好的保鲜效果,为生态复合保鲜膜的研发与果蔬保鲜提供参考。

砂光处理对翅荚木表面特性影响研究

以17年生翅荚木人工林木材为研究对象,对不同粒度砂光与涂饰处理前后的木材材色、表面粗糙度、表面润湿性及表面光泽度进行测定分析。结果表明:翅荚木人工林木材属于高明度、浅红色、高饱和度的黄色调为主的木材,不同粒度砂光处理对涂饰处理前后翅荚木人工林木材各色度学指标的影响均很小。砂光处理砂纸粒度从120目增至240目,翅荚木人工林木材表面Ra、Rz和Rsm随着砂纸粒度的增大均显著减小,而砂纸粒度从240目增至400目,Ra、Rz和Rsm随着砂纸粒度的增大变化均很小。翅荚木人工林木材表面自由能和润湿性随砂纸粒度的增大而增大。涂饰处理后,翅荚木人工林木材表面光泽度明显增大,经醇酸清漆和聚氨酯清漆涂饰处理后,表面光泽度分别在砂纸粒度为320目、400目时增幅最大。

Algorithm and System of Scanning Color 3D Objects

This paper presents a complete system for scanning the geometry and texture of a large 3D object, then the automatic registration is performed to obtain a whole realistic 3D model. This system is composed of one line strip laser and one color CCD camera. The scanned object is pictured twice by a color CCD camera. First, the texture of the scanned object is taken by a color CCD camera. Then the 3D information of the scanned object is obtained from laser plane equations. This paper presents a practical way to implement the three dimensional measuring method and the automatic registration of a large 3D object and a pretty good result is obtained after experiment verification.

基于颜色直方图的电路板表面缺陷检测

为了提高废旧电路板的回收再利用率,针对回收电路板常见表面缺陷,在均匀分块基础上,提出了四叉树分裂颜色直方图缺陷检测方法。该方法能快速定位电路板表面缺陷,并通过支持向量机(SVM)实现缺陷分类,进而为电路板的二次利用提供质量保障。重点分析了分块大小与判断阈值对缺陷定位结果的影响,在保证检测精度的同时,检测速度相比均匀分块方法得到明显提升。与Faster-RCNN网络方法进行对比,结果表明该方法定位效果好,分类准确率平均达81%。

正交试验结合响应曲面法优化辣椒红色素的提取工艺

为优化超声辅助热浸提辣椒红色素的工艺,选用“北京红”辣椒为原料,通过正交试验和响应曲面法分析超声时间、超声温度、料液比、热浸温度、热浸时间和提取次数对产品色价的影响,确定最佳提取工艺。采用皂化去酯法对所得辣椒红色素进一步纯化。试验结果表明,超声时间、超声温度、热浸提时间对辣椒红色素色价有显著影响,以超声时间29 min,超声温度49℃,料液比1∶6,热浸温度60℃,热浸时间1.5 h,提取1次,辣椒红色素粗品色价最高,可达172±6,皂化去酯后色价达到989±25。研究为辣椒红色素的提取工艺优选提供依据。

浅色聚酰胺6抗静电纤维母粒制备及性能

使用硬脂酸(SA)改性纳米锑掺杂二氧化锡包覆二氧化钛(ATO@TiO_(2))作为浅色导电填料,采用熔融共混法制备浅色抗静电聚酰胺6(PA6)纤维母粒。通过扫描电子显微镜、电阻率测试仪、测色仪、热重分析仪等研究ATO@TiO_(2)在PA6基体中的分散情况及其对母粒导电性、白度、热稳定性的影响。实验结果表明,SA改性剂显著提高了ATO@TiO_(2)的疏水性,改善了ATO@TiO_(2)与PA6基体相容性,并提高了ATO@TiO_(2)在PA6中的分散均匀性;当SA质量分数为0.5%时,SA改性ATO@TiO_(2)(SA-ATO@TiO_(2))接触角显著增加到135.65°。当SA-ATO@TiO_(2)体积分数为50%时,显著降低了PA6母粒电阻率,展现出优异的导电性。此外,SA-ATO@TiO_(2)的加入改善了PA6母粒的热稳定性,提高了PA6冷结晶温度。颜色测试表明,尽管SA-ATO@TiO_(2)含量的增加使母粒明度略有下降,但材料仍保持较好的白度。采用复合纺丝法制备浅色PA6抗静电纤维,通过电阻率测试仪、单丝强力仪等研究改性前后ATO@TiO_(2)纤维母粒对纤维力学性能和抗静电性能的影响。实验结果表明,与ATO@TiO_(2)相比,SA-ATO@TiO_(2)制备的浅色PA6抗静电纤维在保持纤维强度的同时显著地降低了纤维单位电阻,纤维单位电阻下降为4.24×10^(9)Ω/cm。

木塑复合材料颜色调控研究现状及展望

随着木塑复合材料(WPCs)在市政园林、汽车和船舶制造等应用领域的快速拓展,市场对木塑制品外观颜色要求也逐渐多元化,颜色调控成为WPCs领域的研究热点,因此,研究WPCs颜色调控方法及其对WPCs性能的影响规律、分析WPCs颜色变化影响因素及揭示颜色调控机理具有重要意义。综述了目前WPCs颜色调控的研究进展,从制备原料、制备工艺和老化变色等方面对影响WPCs颜色变化的因素及及机理进行了梳理;分析了表面覆膜、制备复合表层和添加颜料等颜色调控的3种方法,并从颜色及表面形貌、力学和物理性能等方面分析了颜色调控对WPCs性能的影响,最后,结合WPCs颜色调控研究发展趋势以及未来研究工作重点进行了总结与展望。

高产色素低产桔青霉素红曲霉菌筛选及发酵工艺优化研究

该研究通过扩大菌株分离源,选育优质红曲霉菌M7-5。以该菌株为发酵菌株,采用单因素试验研究大米糊化水量、发酵温度、碳源种类及添加量、氮源种类及添加量对红曲发酵色价及桔青霉素含量的影响,在此基础上,利用响应面试验优化最佳控制参数。结果表明,红曲最佳发酵条件为大米糊化水量13%、甘油添加量8%、硝酸钠添加量1.85%,在此条件下,色价与桔青霉素含量的比值(p/c值)达到22158.2。该研究可为传统红曲发酵工艺的改进和工业化应用提供参考。

超声波改善涤棉织物的色牢度

深色涤棉织物在染色过程中存在染料上染饱和的问题,从而导致织物色牢度差,在超声波的作用下探究织物的皂洗优化工艺:频率35 kHz,功率0.6 W/cm^(2),水温60℃,车速28 m/min。结果表明:超声波皂洗工艺色牢度较传统皂洗工艺有所提升,特别是耐湿摩擦色牢度提升0.5级,节水且节能。