市场营销对中国钻石市场发展的影响

钻石首饰零售业是钻石业的终端环节, 是商品零售业的一部分, 它在中国起步较晚, 但发展较快. 由于中国经济发展、社会稳定, 人们对钻石首饰的需求不断提升, 这对中国钻石零售业提出了更高的要求. 经过DTC钻石贸易公司在中国的市场推广工作, 中国钻石首饰零售业已初具规模, 为进一步发展打下了基础.     

钻石基础知识与销售技巧（二）

钻石被人们认为是无价之宝,其实钻石的价值可以通过钻石的评价要素(4C)来确定。“4C”是决定钻石的品质和价值的标准。 5、怎样衡量钻石的价值“4C”是指钻石的:克拉重量(Carat Weight)、净度(Clarity)、颜色(Colour)、车工(Cut)。重量(Carat Weight): 钻石的重量是4C中最容易量度的特征,与其它     

正确认识4C寻找梦想钻石

钻石这个“宝石之王”已经不再是高不可及了,随着国家钻石分级标准的执行,现今的顾客已经很清楚用4C(切工、克拉重量、净度和色度)衡量钻石价值的诀窍,兴许钻石给人的主要印象是它的璀璨剔透,人们在了解了4C后,对于钻石级别的追求就变得异乎寻常的突出。有关调查显示目前中国市场消费者尤其看重净度和色泽,而忽略切工和克拉重量。如何正确理解4C、运用4C购买合适的钻石首饰,应当是消费者关注的热点。一.钻石的美丽源自良好的切工钻石的切工(Cut)是4C中唯一直接受人为因素影响的一     

寻找闪亮的那一颗--最新"钻石分级"国家标准出台

钻石珍贵罕有而独一无二．恒久的特质让每对情侣为之感怀．璀璨的光芒让每个人为之心醉。而欣赏一颗钻石就好比观摩一位美丽的女子．内涵韵致、音容相貌等多项丽质的巧妙搭配才成就一位绝妙佳人．钻石的魅力并不取决于单一的品质．而需由四个特定评价指数4C和钻石本身内含的情感质素的综合构成来散发．了解钻石必不可少的四大特性．你就能够找到与你自己最匹配、最合适的那一颗．让它与你的美一起灿烂眩目．直至永恒!     

理想切工的完美钻石

对于钻石,中国人正在以惊人的速度追赶世界潮流。从陌生到了解,从了解到熟悉。如今,中国消费者对钻石的4C资讯已经家喻户晓。钻石品质的4个“C”:切工(Cut)、克拉重量(Carat)、颜色级别(Color)、净度(Clarity),是综合评价一颗钻石的基本要素。随着戴比尔斯钻石推广中心1993年开始的针对中国大陆的推广宣传,消费者对钻石逐步加深了解,大陆的钻石市场蓬勃发展。     

宝怡珠宝:唯一南非政府认证尊享臻品美钻之璀璨

正随着网络的发达及零售市场的普及,消费者对钻石的认知度与专业度不断提高,4C的概念也已深深地为消费者所接受,成为他们在选购钻石时的标准。如今,在珠宝零售市场上,如营业员只通过4C标准与顾客进行沟通,在销售分数段较大的钻石时,会受到一定的阻力,并陷入价格的沼泽。各大零售商不得不在钻石销售上拼价格、拼服务、拼款式,导致品牌区隔越来越模糊,     

推广国家标准，快捷服务客户——国检中心与长宁钻石座谈会在京举行

2010年11月13日上午，由国家珠宝玉石质量监督检验中心与深圳市长宁钻石股份有限公司联合举办的“推广国家标准，快捷服务客户——国检中心与长宁钻石合作．力推钻石业再上新台阶”座谈会在北京中国国际展览中心举行。此次会议由国家珠宝玉石质量监督检验中心副主任杨似三主持，主要围绕国检中心与长宁钻石如何就NGTC国际钻石交易平台为钻石行业零售商提供服务展开讨论．国检中心主任毕立君、长宁钻石董事长王宁等相关业内人士发了言。     

钻石的4C特征是销售的法宝还是障碍——让你的营业员重新认识钻石的4C

钻石的4C特征应该成为钻石首饰销售的有利武器和法宝，还是变成了钻石首饰销售的障碍？无论是钻石批发商还是钻石零售商，亦或是营业员，肯定都希望钻石的4C特征成为销售钻石的有利武器和法宝。可是，在实际经营、销售过程中，由于营业员对4C的使用不当，“事与愿违”地把钻石的4C特征逐渐变成了阻碍销售的因素。     

钻石基础知识与销售技巧（三）

本刊前两期详细介绍了钻石基础知识,使读者了解了钻石的基本特性。但是仅仅掌握了钻石的特点及4C图表,对于一个专业的钻石营业员来说,还是远远不够的。因为你旨在有信心达成更佳的买卖。要达成交易,你要将钻石的特点,向顾客传达,不仅要顾客了解钻石的特点,更重要的是向顾客解释其优点,这样才使你成为更加专业的钻石营业员及可能销售更多的钻石。     

钻石还是消费者的最爱吗？

钻石,真的受冷落了吗?当国际钻石珠宝商异口同声地看好中国钻石市场的时候,身在其中的中国钻石商家却深切地感受到眼前激烈竞争的市场带给他们的不确定性。去年圣诞节那一天,河南许昌金九福钻石专卖店,几个导购闲散地站在柜台里面,没有生意     

Relationship between structural development of cell walls and degradation of tissues in maize stems

Sections of internodes of growing maize stems were used to study the behaviour of cell walls of different tissues during in-vitro degradation with rumen fluid. Tissues with primary cell walls-middle lamellae, at early stages of development, were degraded completely. In specific tissues, newly synthesised secondary walls were highly digestible whereas the primary walls-middle lamellae of these tissues were indigestible. These primary walls-middle lamellae stained positively with acid phloroglucinol but showed no fluorescence. At pollination, when secondary walls were of considerable thickness, these walls were still completely digestible even though they stained intensely with acid phloroglucinol and showed reduced fluorescence. However, at some distance from the cut end of sections, the secondary walls of the elongated tube-like cells of sclerenchyma tissue showed considerable reduction in digestibility. Cross-sectional area and dry weight measurements of different stem tissues revealed the importance of secondary wall digestion of sclerenchyma compared with the thin-walled parenchyma. Chemical treatment with KmnO₄ or NaOH resulted in colourless secondary walls after staining whereas primary walls still reacted positively. It was concluded that very small amounts of phenolic compounds (lignin) located in the primary wall-middle lamella that are not removed by KmnO₄ and NaOH treatment are responsible for the decrease in digestibility of tissues during plant development. Histochemical ‘lignin’ reactions and fluorescence just detect phenolic compounds and cannot be correlated with degradation.     

Genetic basis of secondary type traits for Holsteins

Classifications from the Holstein Association were for secondary and primary type traits. Full linear scale of 1 to 50 was used for primary type traits, but scores for secondary type traits perceived to be midscale (21 to 29) were not recorded. Scores for midscales were randomly assigned to cows based on normalized sire distributions from percentages of daughters scored 1 to 20 and 30 to 50. Procedure for assigning scores of 21 to 29 was tested with primary type traits and judged satisfactory. Estimates of heritability for secondary type traits agreed favorably with earlier estimates. Only three secondary type traits had heritability of at least .15, and they were relative height of front end, teat placement side view, and tailhead. Heritabilities for traits of legs and feet were uniformly low, and traits of legs and feet were closely related. Little practical gain was anticipated from selection for secondary type traits.     

Effect of delaying budburst on shoot development and yield of Vitis vinifera L. Chardonnay ‘Mendoza’ after a spring freeze event

Background and Aims: Spring freeze events can result in substantial grapevine yield losses in many parts of the world. Understanding vine responses following early spring freeze events will aid in the development of decision support systems for vineyards damaged by freezing temperatures. Methods and Results: The date of budburst of spur‐pruned Chardonnay vines was manipulated by pruning time and/or the application of sodium alginate gel. A spring freeze event occurred at bud swell/woolly bud, killing 33% of the developing shoots. Treatments that delayed bud development expressed a lower incidence of freeze damage (as low as 3%). Where primary shoots had been killed, secondary shoots developed in their place. The yield from secondary shoots was 32% of that from primary shoots, with the majority of fruiting secondary shoots bearing only one bunch. Average bunch weight, number of berries per bunch and average berry weight of secondary shoots were comparable with those from primary shoots. Conclusions: The damage to primary shoots caused by early spring freeze events can be reduced by using treatments that delay bud development. Secondary shoots develop in response to death of the primary shoot, and although they have reduced fruitfulness, they can partially mitigate the potential yield losses associated with the death of primary shoots. Significance of the Study: The number and fruitfulness of secondary shoots that develop after a spring freeze event determine the extent of mitigation of yield losses associated with the death of primary shoots.     

Polycyclic aromatic hydrocarbon and particulate emissions from two-stage combustion of polystyrene: the effect of the primary furnace temperature

A study is presented on laboratory-scale combustion of polystyrene (PS) to identify staged-combustion conditions that minimize emissions. Batch combustion of shredded PS was conducted in fixed beds placed in a bench-scale electrically heated horizontal muffle furnace. In most cases, combustion of the samples occurred by forming gaseous diffusion flames in atmospheric pressure air. The combustion effluent was mixed with additional air, and it was channeled to a second muffle furnace (afterburner) placed in series. Further reactions took place in the secondary furnace at a residence time of 0.7 s. The gas temperature of the primary furnace was varied in the range of 500-1,000 degrees C, while that of the secondary furnace was kept fixed at 1,000 degrees C. Sampling for CO, CO2, O2, soot, and unburned hydrocarbon emissions (volatile and semivolatile, by GC-MS) was performed at the exits of the two furnaces. Results showed that the temperature of the primary furnace, where PS gasifies, is of paramount importance to the formation and subsequent emissions of organic species and soot. Atthe lowesttemperatures explored, mostly styrene oligomers were identified at the outlet of the primary furnace, but they did not survive the treatment in the secondary furnace. The formation and emission of polycyclic aromatic hydrocarbons (PAH) and soot were suppressed. As the temperature in the first furnace was raised, increasing amounts of a wide range of both unsubstituted and substituted PAH containing up to at least seven condensed aromatic rings were detected. A similar trend was observed for total particulate yields. The secondary furnace treatment reduced the yields of total PAH, but it had an ambiguous effect on individual species. While most low molecular mass PAH were reduced in the secondary furnace, concentrations of some larger PAH increased under certain conditions. Thus, care in the selection of operating conditions of both the primary furnace (gasifier/ burner) and the secondary furnace (afterburner) must be exercised to minimize the emission of hazardous pollutants. The emissions of soot were also reduced in the afterburner but not drastically. This indicates that soot is indeed resistant to oxidation; thus, it would be best to avoid its formation in the first place. An oxidative pyrolysis temperature of PS in the vicinity of 600 degrees C appears to accomplish exactly that. An additional afterburner treatment at a sufficiently high temperature (1,000 degrees C) may be a suitable setting for minimization of most pollutants. To obtain deeper understanding of chemical processes, the experimental results were qualitatively compared with preliminary predictions of a detailed kinetic model that describes formation and destruction pathways of chemical species including most PAH observed in the present work. The modeling was performed forthe secondary furnace assuming plug-flow conditions therein. The experimentally determined chemical composition at the outlet of the primary furnace was part of the input parameters of the model calculation.     

Dynamic predictive model for growth of Salmonella enteritidis in egg yolk

ABSTRACT:  Salmonella Enteritidis (SE) contamination of poultry eggs is a major human health concern worldwide. The risk of SE from shell eggs can be significantly reduced through rapid cooling of eggs after they are laid and their storage under safe temperature conditions. Predictive models for the growth of SE in egg yolk under varying ambient temperature conditions (dynamic) were developed. The growth of SE in egg yolk under several isothermal conditions (10, 15, 20, 25, 30, 35, 37, 39, 41, and 43 °C) was determined. The Baranyi model, a primary model, was fitted with growth data for each temperature and corresponding maximum specific growth rates were estimated. Root mean squared error (RMSE) values were less than 0.44 log₁₀ CFU/g and pseudo- R ² values were greater than 0.98 for the primary model fitting. For developing the secondary model, the estimated maximum specific growth rates were then modeled as a function of temperature using the modified Ratkowsky's equation. The RMSE and pseudo- R ² were 0.05/h and 0.99, respectively. A dynamic model was developed by integrating the primary and secondary models and solving it numerically using the 4th-order Runge–Kutta method to predict the growth of SE in egg yolk under varying temperature conditions. The integrated dynamic model was then validated with 4 temperature profiles (varying) such as linear heating, exponential heating, exponential cooling, and sinusoidal temperatures. The predicted values agreed well with the observed growth data with RMSE values less than 0.29 log₁₀ CFU/g. The developed dynamic model can predict the growth SE in egg yolk under varying temperature profiles.     

“PLEASE PASS THE CHICKEN TITS”: RETHINKING MEN AND COOKING AT AN URBAN FIREHOUSE

Women, for centuries, have been the primary cooks and nurturers in most cultures. Men rarely represent family primary food providers. My interest in this study lies in what happens when men who are not food professionals develop into this role of primary cooks for a group of people; in this case, the men of an urban firehouse. Men in this scenario perform in roles typically ascribed to both men and women, and when a woman is involved, her presence is mitigated. I found that the men created a unique food system, and while each brought intact a value system and ethnic heritage to the table, these packages became negotiated, most powerfully in the kitchen and at meals. I was interested in how these men performed in roles that, in our mass consciousness and popular culture, we often ascribe to women. How do they shop, cook, and eat? How do they feel about what they are doing? How and why do they choose to cook? What issues do they face with regard to their identity as men, and how does this influence their food choices, cooking, and eating? Firehouse cooks perform domesticity by relying on multiple versions of masculinity at home and in the fire station.     

Determination of the growth limits and kinetic behavior of Listeria monocytogenes in a sliced cooked cured meat product: validation of the predictive growth model under constant and dynamic temperature storage conditions

To describe the growth limits of Listeria monocytogenes NCTC10527 in a sliced vacuum-packaged cooked cured meat product, the binary logistic regression model was used to develop an equation to determine the probability of growth or no growth of L. monocytogenes as a function of temperature (from 0 to 10 degrees C) and water activity (from 0.88 to 0.98). Two inoculum concentrations were used (10 and 10(4) CFU g(-1)), and the growth limits for the two inocula were different. The kinetic behavior of L. monocytogenes as a function of temperature (4, 8, 12, and 16 degrees C) on the same meat product at the lower concentration (10 CFU g(-1)) was also studied. The Baranyi model appeared to fit the overall experimental data better than did the modified Gompertz and the modified logistic models. Maximum specific growth rate (micromax), lag phase duration (LPD), and maximum cell concentration (Nmax) derived from the primary model were modeled using the square root function (micromax and LPD) and a second order polynomial (Nmax) (secondary models). The selection of the best model (primary or secondary) was based on some statistical indices (the root mean square error of residuals of the model, the regression coefficient, the F test, the goodness of fit, and the bias and accuracy factor). The developed kinetic behavior model was validated under constant and dynamic temperature storage conditions. This prediction of L. monocytogenes growth provides useful information for improving meat safety and can be used for in-depth inspection of quality assurance systems in the meat industry.     

Characterization of organic compounds collected during southeastern aerosol and visibility study: water-soluble organic species

As part of the Southeastern Aerosol and Visibility Study (SEAVS), water-soluble organic species (WSOS) in fine aerosols collected from July 15 to August 25, 1995, at the Great Smoky Mountain National Park, Tennessee (USA), were chemically classified into seven groups, with concentrations ranging from around 1 to >200 ng/m3. Dicarboxylic acids represented the dominant identified compound class, and succinic acid was the most abundant dicarboxylic acid. The trends in data suggest that most WSOS collected in the SEAVS samples were mainly generated from secondary photochemical reactions, especially during the first (cleaner) half of the sampling campaign. High relative humidity at the sampling site resulted in substantial water uptake by the aerosols, which may have enhanced the levels of succinic acid by reducing its rate of photooxidation. Concurrent trends in malic and malonic acid concentrations suggest these were generated from the oxidation of succinic acid. Consistent with the conversion of 3-hydroxypropanoic acid to malonic acid, it appears that 4-hydroxybutanoic acid served as a major precursor contributing to high levels of succinic acid in the daytime. Nocturnal WSOS generally followed the trend of diurnal WSOS, but they exhibited different chemical compositions and lower concentrations, unlike what has been reported for an urban site. A nocturnal-to-diurnal ratio of succinic acid larger than 0.25 may indicate an atmosphere dominated by photochemical reactions, rather than by primary emissions.     

A predictive microbiology approach for thermal inactivation of Hepatitis A virus in acidified berries

Hepatitis A virus (HAV) is a food-borne enteric virus responsible for outbreaks of hepatitis associated with consumption of raw vegetables. Soft fruits, such as red berries, exposed to faecal contamination are increasingly responsible for collective food-borne illnesses associated with HAV, when eaten raw or used in unprocessed foods. Heat is the most effective measure for the inactivation of HAV. Thermal treatments are used on fruits as a decontamination method, but they have to be adapted to product characteristics; indeed, factors such as sugar or pH may have an impact on the viral sensitivity to thermal treatments. A model was developed for the inactivation of HAV in red berries without supplemented sugar and with different pH values. Nonlinear inactivation curves in acidified raspberries were modelled using an integrated model, with a single equation nesting secondary models of temperature and pH in the primary model. Model predictions were then confronted to experimental results obtained in another laboratory on other berries with different pH values. Excellent predictions were obtained in most cases, while failed predictions provided safe results, with the model predicting higher residual virus titres than what was observed.     

Ozone-initiated secondary emission rates of aldehydes from indoor surfaces in four homes

Field experiments were conducted in four homes during summerto quantify ozone-induced secondary emission rates (SERs) of aldehydes on indoor surfaces. Four surfaces in each house were examined: living room carpet, living room wall, kitchen floor, and kitchen counter. Upon exposure to ozone for 3 h, formaldehyde and C3-C10 saturated aldehydes, especially nonanal, were emitted as products of ozone-surface reactions. Carpet in newer homes had higher SERs than carpet in older homes. For example, the nonanal SER from the living room carpet was 80 microg m(-2) h(-1) in a 1 year old home, but only 8-20 microg m(-2) h(-1) in two homes that were greater than 10 years old. All kitchen countertops were very reactive and high SERs were observed, especially for nonanal. Product yields from countertops were consistent with the products of ozone reactions with oleic and linoleic esters, common in cooking oils. These findings suggest that carpet surfaces become depleted of reactants as they become oxidized over time. However, countertop surfaces, which are cleaned frequently or become covered in cooking oils, are continuously replenished with reactants. Over time, countertops may become the dominant contributor to indoor concentrations of secondary aldehydes. However, when total surface area is taken into account for the homes assessed, carpet is predicted to be the primary source of secondary emissions, even for older homes.