The Laboratory Balance (re J. Chem. Educ. 2001, 78, 434)

2002 ◽  
Vol 79 (5) ◽  
pp. 559
Author(s):  
F. Axtell Kramer
Keyword(s):  
Laboratory Balance

An elementary chemistry laboratory balance

1930 ◽  
Vol 7 (1) ◽  
pp. 127
Author(s):  
Showell C. Dennis ◽  
Webster H. Hansen
Keyword(s):  
Chemistry Laboratory ◽  
Laboratory Balance

Assessment of commodity and consumer qualities of fruits of promising apricot forms

2021 ◽  
Vol 67 ◽  
pp. 60-68
Author(s):  
R. Ye. Bogdanov
Keyword(s):  
Fruit Size ◽  
Weight Ratio ◽  
Fruit Weight ◽  
Soluble Solids ◽  
Fruit Peel ◽  
Microsoft Excel ◽  
Scientific Center ◽  
Fruit Skin ◽  
Laboratory Balance ◽  
High Level

The purpose of researches was the assessment of commodity and consumer qualities for fruit of promising apricot forms which have been bred in the Michurin Federal Scientific Center. 8 apricot genotypes breeding in this institution were studied. The regionalized variety U’lyanikhinsky with its high level of commercial consumer qualities of fruit was used as a control. Fruit skin strength was assessed at the stage of consumer maturity using an FT30 penetrometer with a plunger diameter of 8 mm. Weighing was carried out on an AND EJ-6100 laboratory balance. The content of soluble solids was determined with an MT-032ATS field refractometer. Statistical data processing was carried out using computer programs Microsoft Excel 2007, Statistics. The largest fruit size was marked in Cezar variety. Average and maximum weights were 42.3 and 59.1 g, respectively. The least stone-to-fruit weight ratio (6.6 %) was found in Viking variety. The sample varieties Cezar, elite forms №1 and 3-5-7 are considered to be as freestone apricots. Elite form No. was characterized by an excellent taste of fruit. The fruits of the control variety «U’lyanikhinsky» and elite forms №1, 1-1-24 were distinguished by a strong juiciness of the pulp. The extremely rich fruit texture was observed in control variety U’lyanikhinsky and in Cezar variety, elite form № 3-5-7. The fruit of varieties Cezar, Viking and elite form No. 1 had the firmest fruit peel. The aforementioned apricots combined the attractiveness of fruits, their one — dimensional ground color with bright over color. Under the circumstances of the Central chernozem region the varieties Cezar, U’lyanikhinsky, Viking and elite form No. 1 pay attention to their high commodity and consumer qualities of fruit.

scholarly journals Granulometric composition research of mine rocks as a material for backfilling the mined-out area in coal mines

2021 ◽  
Vol 15 (4) ◽  
pp. 122-129
Author(s):  
Mykhailo Petlovanyi ◽  
Dmytro Malashkevych ◽  
Kateryna Sai ◽  
Ievgeniia Bulat ◽  
Vasyl Popovych
Keyword(s):  
Granulometric Composition ◽  
Digital Processing ◽  
Laboratory Research ◽  
Sieve Analysis ◽  
Backfill Material ◽  
The Face ◽  
Analysis Laboratory ◽  
Laboratory Balance ◽  
Granulometric Characteristics

Purpose. Determination of the granulometric characteristics and loosening coefficient of mine rocks formed during stope operations from undercutting the bottom rocks as a potential backfill material based on a set of mine and laboratory research. Methods. To do research, a complex methodology is used, which includes a photographic surveying the mass of destroyed rocks from undercutting the bottom rocks in mine conditions, digital processing and determining the granulometric composition in the software package, sampling the mine rocks at the surface complex, and reconstructing the granulometric composition, similar to the full-scale mine conditions in the laboratory. Sieve analysis, laboratory balance and laboratory container are used to determine the granulometric composition and loosening coefficient. Findings. The dependence between the granulometric composition and loosening coefficient of rocks, which increases by 33% within fractions of 0-50 mm and by 8% within fractions of 50-140 mm, has been revealed. It has been determined that the destroyed rocks in the face within fractions of 0-140 mm have a bulk density of 1.28 g/cm3, loosening coefficient of 1.7, the voidness of and the maximum reserve for the backfill mass compaction with mine rocks is 41.9%. An analytical assessment of the volumes of the formed cavities of the mined-out area in the longwall face and gobed mine workings, as well as the prospects and completeness of their filling with mine rocks have been performed. Originality. It has been determined that the loosening coefficient of mine rocks destroyed in the stope face by KA-200 shearer changes according to the logarithmic dependence on their granulometric composition. This makes it possible to control the granulometric characteristics of the backfill material to achieve the maximum density of the backfill mass. Practical implications. Further research can serve as a basis for determining the rational parameters for the formation and placement of backfill masses during complex-mechanized selective mining of coal seams using various methods of backfilling operations.

Unrecoverable bi-products of drilling titanium alloy and tantalum metal implants: a pilot study

2018 ◽  
Vol 28 (5) ◽  
pp. 531-534 ◽  
Author(s):  
Paweł Skowronek ◽  
Paweł Olszewski ◽  
Wojciech Święszkowski ◽  
Marek Synder ◽  
Marcin Sibiński ◽  
...  
Keyword(s):  
Titanium Alloy ◽  
In Vitro Study ◽  
Drilling Process ◽  
Trabecular Metal ◽  
Metal Implants ◽  
Porous Architecture ◽  
Laboratory Balance ◽  
Adverse Influence ◽  
Drill Holes

Background: Trabecular metal implants with a porous architecture that allows for the incorporation of bone into the implant during healing are gaining popularity in alloplastic revision procedures. The bi-products of drilling titanium alloy (Ti) and tantalum (Ta) implants have not been previously assessed. Methods: Four holes were drilled in each of 2 spatially porous trabecular implants, one Ta and the other Ti alloy (Ti-6Al-7Nb), for this pilot in vitro study. The particles were flushed out with a continuous flow of saline. The particles’ weight and the volume were then measured using a Radwag XA 110/2X (USA) laboratory balance. The total volume of the obtained metal fines was measured by titration using a 10 mm3 measurement system. Results: A cobalt carbide bit was used since the holes could not be made with a standard bone drill. Each Ti and Ta implant lost 1.26 g and 2.48 g of mass, respectively. The volume of free particles recovered after each stage was 280 mm3 and 149 mm3, respectively. Approximately 0.6% of the total implant mass was not recovered after drilling (roughly 2% of the mass of the particles created by drilling), despite the use of 5 µm filters. Conclusions: It is technically difficult to drill holes in Ti and Ta implants using standard surgical tools. The drilling process creates a considerable amount of metal particles, which cannot be recovered despite intensive flushing. This may have an adverse influence on the bio-functionality (survival) of the endoprosthesis and present deleterious systemic consequences.

scholarly journals ENGINELESS METHODS OF THE ESTIMATION OF OPERATIONAL PROPERTIES FUELSFOR AGRICULTURAL MACHINERY

2021 ◽  
pp. 110-115
Author(s):  
С.А. ПЛОТНИКОВ ◽  
П.В. ГНЕВАШЕВ ◽  
Г.П. ШИШКИН ◽  
Е.Н. РЕЗНИК
Keyword(s):  
Refractive Index ◽  
Physicochemical Parameters ◽  
Rapeseed Oil ◽  
Alternative Fuels ◽  
Motor Fuel ◽  
Laboratory Equipment ◽  
Mixed Fuel ◽  
External Conditions ◽  
Laboratory Balance ◽  
Cold Pressed

Проблема и цель. В ходе проведенного обзора литературы было установлено, что между основными эксплуатационными свойствами моторного топлива и его физико-химическими показателями существуют корреляционные зависимости. Логично предположить, что подобные зависимости могут быть применимы и к альтернативному топливу. Цель исследований – определение физико-химических показателей смесевого топлива, влияющих на эксплуатационные характеристики дизельного двигателя. Объекты и методы. Объект исследований – смеси товарного дизельного топлива с рапсовым маслом холодного отжима. Исследовались физико-химические показатели смесевого топлива с различным содержанием рапсового масла. Массовая доля рапсового масла в искомой смеси варьировалось от 0 до 50 %. Для измерения показателей использовалось специализированное лабораторное оборудование – пикнометр ПЖ-2-25, лабораторные весы VIBRAAJH-620CE и рефрактометр ИРФ-454б. Ход экспериментов. Значения плотности и показателя преломления фиксировались для каждой подготовленной смеси. Данные эксперимента и последующих расчетов наносились на графики. По данным плотности и показателя преломления был построен график удельной рефракции Лорентца-Лоренца. Результаты и выводы. В результате анализа полученных данных лабораторных опытов было установлено, что некоторые выходные показатели работы ДВС на альтернативных топливах могут существенно зависеть от физических показателей, измеренных в ходе эксперимента, что позволяет найти корреляционные зависимости между ними. В качестве экспресс-метода оценки эксплуатационных свойств двигателя предложено использовать удельную рефракцию, так как она проста в определении, не зависит от внешних условий и позволяет использовать её на месте эксплуатации. Problem and purpose. In the course of the literature review, it was found that there are correlations between the main operational properties of motor fuel and its physicochemical indicators. It is logical to assume that similar dependences can be applied to alternative fuels. The purpose of the research is to determine the physicochemical parameters of the mixed fuel that affect the performance of a diesel engine. Objects and Methods. The object of research is a mixture of commercial diesel fuel with cold-pressed rapeseed oil. The physicochemical parameters of mixed fuel with different rapeseed oil content were studied. The mass fraction of rapeseed oil in the desired mixture varied from 0% to 50%. To measure the indicators, specialized laboratory equipment was used - a PZh-2-25 pycnometer, a VIBRAAJH-620CE laboratory balance and an IRF-454b refractometer. The course of experiments. The values of density and refractive index were recorded for each prepared mixture. The experimental data and subsequent calculations were plotted on graphs. Based on the density and refractive index data, a graph of the Lorentz-Lorentz specific refraction was plotted. Results and conclusions. As a result of the analysis of the obtained data of laboratory experiments, it was found that some output indicators of the ICE operation on alternative fuels can significantly depend on the physical indicators measured during the experiment, which makes it possible to find correlations between them. As an express method for assessing the operational properties of the engine, it is proposed to use the specific refraction, since it is easy to determine, does not depend on external conditions and allows it to be used at the site of operation.

scholarly journals EFFECTS OF WEATHER AND AGRICULTURAL TECHNIQUES ON RIPENING OF SPRING DURUM WHEAT IN THE ORENBURG PRIURALIYE

2019 ◽  
Vol 4 (2) ◽  
pp. 8-15
Author(s):  
Ишен Бесалиев ◽  
Ishen Besaliev ◽  
Александр Панфилов ◽  
Aleksandr Panfilov
Keyword(s):  
Durum Wheat ◽  
Central Zone ◽  
Weather Conditions ◽  
Dry Matter Accumulation ◽  
Yield And Quality ◽  
Grain Moisture ◽  
Laboratory Balance ◽  
Favorable Weather ◽  
Two Stages

The aim of the study is to increase the yield of spring durum wheat in the Orenburg Urals. Spring hard wheat makes more demands on the temperature region during the formation and filling of grain. Due to the growing aridity conditions of the second half of the growing season, when the grain falls asleep, have become more unfavorable. As you know, the nature of the filling, favorable weather conditions in this period are determined by the yield and quality of grain. The studies were carried out in 2016-2018 in the Central zone of the Orenburg region on chernozems ordinary in two stages of the main tillage. Weather conditions contrasted sharply. The research method is a field experiment. Experience and research were conducted according to conventional methods. Analysis of the grain samples was performed using a laboratory balance Adam NSV 602N and furnace SESH-3M. Mathematical analysis was performed in the program Statistica 6.0. It is established that the duration of grain loading in the study area depends on the weather conditions of the year, ranging from 20-21 days to 31 days. The growth rate of dry matter accumulation in durum wheat grain is observed in the air temperature range 18.7-26.2°C, followed by an increase in temperature reduces the increase. Amid the subsurface processing plowed fields, reducing grain moisture is less intense: 10 grade Orenburg-plowing is of 0.99 – 2.46% on a day, subsurface tillage-0.80 – 2.50% daily; cultivar bezenchukskaya 210 – plowing 1.64-of 2.34%, subsurface tillage-1.03-2.32%.

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