scholarly journals Field Reaction Experiments of Carbonate Minerals in Spring Waters: Natural Analogue of Geologic CO2 Storage

Geofluids ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
Masao Sorai ◽  
Munetake Sasaki ◽  
Takahiro Kuribayashi
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Co2 Storage ◽  
Reaction Rates ◽  
Trapping Rate ◽  
Natural Analogue ◽  
Carbonate Minerals ◽  
Slow Growth Rate ◽  
The Difference ◽  
Mineral Trapping

To diminish the uncertainty of the mineral trapping rate during geologic CO2 storage, the growth rate of carbonate minerals was measured in CO2-containing spring waters, which can be regarded as a natural analogue of geologic CO2 storage. The authors’ approach, using nanoscale analysis of seed crystal surfaces after immersion into spring waters, enables rapid and accurate measurement of mineral reaction rates. The results show that calcite growth rates in spring waters were lower by 1–3 orders than the values given in a database of laboratory experiment results. We verified the traditional paradigm that Mg2+ controls carbonate reaction kinetics. An increase of the Mg/Ca ratio to around 5 by adding Mg2+ to spring waters markedly reduced the calcite growth rate. However, even if effects of Mg2+ and flow rate are considered, we were unable to explain satisfactorily the difference of the calcite growth rates between those of spring waters and laboratory experiments. Therefore, other factors might also be related to the slow growth rate in nature. The present results, including the fact such that neither dolomite nor magnesite was formed even at the high Mg/Ca ratio, are expected to provide an important constraint to overestimation of the mineral trapping rate.

The Relative Growth of Parts in Palaemon Carcinus

1930 ◽  
Vol 7 (2) ◽  
pp. 165-174
Author(s):  
M. A. TAZELAAR
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Linear Measurements ◽  
Relative Growth ◽  
Male And Female ◽  
Relative Growth Rates ◽  
Rate Of Growth ◽  
The Difference ◽  
Rates Of Growth

Linear measurements of certain appendages and the carapace of P. carcinus were made and plotted in various ways. The following conclusions were drawn: 1. The cheliped shows heterogonic growth in both male and female, but more markedly in the male, the values of k being: male 1.8 and female 1.48 2. The pereiopods in both male and female are slightly heterogonic. The relative growth rates are graded from p3 to p5, that of p3 being slightly greater than that of p5 3. Of the ordinary pereiopods the rate of growth of p1 is the smallest in the male, but the largest in the female. 4. The difference between the rates of growth of p1 and p3 in male and female is greatest where the rate of growth in the heterogonic organ, the cheliped, is most excessive in the male. 5. The growth of the 3rd maxilliped is slightly negatively heterogonic, the value of k in the male being 0.93 and in the female 0.95. Hence there seems to be a correlation between the marked heterogony in the cheliped on the growth rate of neighbouring appendages. In those immediately posterior to the cheliped the growth rate is increased and in those anterior decreased.

scholarly journals Assessing the lockdown effect from excess mortalities

2021 ◽  
Author(s):  
Alexej Weber
Keyword(s):  
Growth Rate ◽  
South Korea ◽  
Growth Rates ◽  
Excess Mortality ◽  
Reproduction Number ◽  
Average Growth Rate ◽  
Average Growth ◽  
Reproduction Numbers ◽  
The Difference ◽  
Pharmaceutical Interventions

AbstractBackground and AimsThe reported case numbers of COVID-19 are often used to estimate the reproduction number or the growth rate. We use the excess mortality instead, showing the difference between most restrictive non-pharmaceutical interventions (mrNPIs) and less restrictive NPIs (lrNPIs) with respect to the growth rate and death counts.MethodsWe estimate the COVID-19 growth rate for Sweden, South Korea, Italy and Germany from the excess mortality. We use the average growth rate obtained for Sweden and South Korea, two countries with lrNPIs, to estimate additional death numbers in Germany and Italy (two countries with mrNPIs) in a hypothetic lrNPIs scenario.ResultsThe growth rate estimated from excess mortality decreased faster for Germany and Italy than for Sweden and South Korea, suggesting that the mrNPIs have a non-negligible effect. This is not visible when the growth rate is calculated using the reported case numbers of COVID-19. This results in approximately 4 500 and 12 000 more death numbers for Germany and Italy, respectively.ConclusionThe reproduction numbers or growth rates obtained from reported COVID-19 cases are most likely biased. Expanding testing capacity led to an overestimation of the growth rate across all countries analyzed, masking the true decrease already visible in the excess mortality. Using our method, a more realistic estimate of the growth rate is obtained. Conclusions made for the reproduction number derived from the reported case numbers like the insignificance of most restrictive non-pharmaceutical interventions (lockdowns) might be wrong and have to be reevaluated using the growth rates obtained with our method.

The effect of management factors on the intestinal bacteria and the growth rate of chicks

1960 ◽  
Vol 55 (1) ◽  
pp. 61-68 ◽  
Author(s):  
B. E. March ◽  
C. Goudie ◽  
Jacob Biely
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Intestinal Bacteria ◽  
Intestinal Wall ◽  
Bacterial Counts ◽  
Retarded Growth ◽  
Management Factors ◽  
The Difference

1. The apparent cleanliness of the premises in which chicks are reared has little bearing on the growth rate of chicks within a given environment.2. Bacterial counts of faeces from chicks reared under clean or extremely contaminated conditions showed no difference between the two sets of conditions.3. Delaying feeding until 72 hr. after hatching retarded growth to at least 7 weeks of age. If the age of the chicks was calculated from the time at which the chicks were fed rather than the date of hatch, the weights of the chicks fed 72 hr. after hatching corresponded with those of the chicks fed immediately.4. The contents of the duodenum and mesenteric intestine showed higher bacterial counts when feeding was delayed for 72 hr. than when feed was given shortly after hatching. This effect was no longer evident after the chicks were 1 week old.5. Administration of penicillin in the water did not reduce the difference in growth rates between the chicks given feed immediately and those from which feed was withheld.6. Antibiotics may decrease the thickness of the intestinal wall without stimulating growth.

The Solute Drag Model to Calculate Grain Growth Rate at High Temperatures in Carbon Steels

2012 ◽  
Vol 706-709 ◽  
pp. 1574-1579 ◽  
Author(s):  
Yasu Yogo ◽  
K. Tanaka ◽  
Hideaki Ikehata ◽  
Noritoshi Iwata ◽  
Kou Nakanishi ◽  
...  
Keyword(s):  
Growth Rate ◽  
Grain Growth ◽  
Growth Rates ◽  
Solute Drag ◽  
Carbon Steels ◽  
Drag Model ◽  
Substitutional Element ◽  
Proposed Model ◽  
Segregation Effect ◽  
The Difference

Based on the solute drag model, a practical model incorporating the segregation effect is proposed to calculate grain growth rates in carbon steels. The segregation effect is modeled using two factors: the difference in atomic diameter between a solvent and a substitutional element, and the solubility of a substitutional element. By including the segregation energy, the proposed model enables the simulated retardation of grain growth by the addition of microalloying elements. The calculated grain growth rate by the proposed model shows reasonable correspondence between grain growth rates for experimental and calculated results. The temperature dependence of the grain growth rate is also well simulated.

scholarly journals Growth of atmospheric clusters involving cluster-cluster collisions: comparison of different growth rate methods

2016 ◽  
Author(s):  
J. Kontkanen ◽  
T. Olenius ◽  
K. Lehtipalo ◽  
H. Vehkamäki ◽  
M. Kulmala ◽  
...  
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Particle Formation ◽  
Vapor Condensation ◽  
Model Substance ◽  
External Conditions ◽  
The Common ◽  
The Difference ◽  
Atmospheric Clusters ◽  
True Values

Abstract. We simulated the time evolution of atmospheric cluster concentrations in a one-component system where clusters grow not only by condensation of monomers, but where also cluster-cluster collisions significantly contribute to the growth of the clusters. Our aims were to investigate the consistency of the growth rates of sub-3 nm clusters determined with different methods, and the validity of the common approach to use them to estimate particle formation rates. We compared the growth rate corresponding to particle fluxes (FGR), the growth rate derived from the appearance times of clusters (AGR) and the growth rate calculated based on irreversible vapor condensation (CGR). We found that the relation between the different growth rates depends strongly on the external conditions and the properties of the model substance. The difference between the different growth rates was typically highest at the smallest, sub-2nm sizes. FGR was generally lower than AGR and CGR; at the smallest sizes the difference was often very large, while at sizes larger than 2 nm, the growth rates were closer to each other. AGR and CGR were in most cases close to each other at all sizes. The difference between the growth rates was generally lower in conditions where cluster concentrations were high, and evaporation and other losses thus less significant. Furthermore, our results show that the conventional method used to determine particle formation rates from growth rates may give estimates far from the true values. Thus, care must be taken not only in how the growth rate is determined, but also in how it is applied.

Relationship of Crack Growth Between Thermal-Mechanical and Isothermal Low-Cycle Fatigue at Elevated Temperatures

1987 ◽  
Vol 109 (2) ◽  
pp. 114-118 ◽  
Author(s):  
Masakazu Okazaki ◽  
Takashi Koizumi
Keyword(s):  
Growth Rate ◽  
Flow Stress ◽  
Crack Growth ◽  
Growth Rates ◽  
Elevated Temperatures ◽  
Low Cycle Fatigue ◽  
J Integral ◽  
Cycle Fatigue ◽  
The Difference ◽  
Crack Growth Rates

The surface and through crack growth behaviors of some steels in thermal-mechanical and isothermal low-cycle fatigue at elevated temperatures were investigated. It was shown that the crack growth rate under each test condition was successfully correlated with the cyclic J-integral range by the simple power law equation, regardless of crack configurations and test controlling modes. Based on the results thus obtained, the relationship between the crack growth rates of the two types of fatigue was discussed. When the crack growth rates in thermal-mechanical and isothermal low-cycle fatigue at elevated temperatures were correlated with the parameter of which the range of cyclic J-integral was divided by the equivalent flow stress defined in this work, they could be represented by a single curve approximately. The crack growth rates in isothermal fatigue under various test temperatures could be also represented by the same single crack growth curve described above, regardless of the test materials. From the above result, it was found that the difference of crack growth rate in both types of fatigue merely resulted from the difference of equivalent flow stress.

Growth and carcass composition of ram and wether lambs fed at two levels of nutrition

1986 ◽  
Vol 26 (3) ◽  
pp. 275 ◽  
Author(s):  
GJ Lee
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Subcutaneous Fat ◽  
Fat Deposition ◽  
Carcass Composition ◽  
Carcass Weight ◽  
High Fat ◽  
Fat Depots ◽  
Ram Lambs ◽  
The Difference

This experiment examined the effects of two levels of nutrition on growth rate and fat deposition in the subcutaneous, kidney plus channel, omental and mesenteric depots of ram and wether second-cross lambs. Growth rates to slaughter were higher (P< 0.001) in lambs fed at the higher level of nutrition (170 � 5 v. 88 � 3 g/day; mean � s.e.). There was no difference in growth rates between ram and wether lambs at the levels of nutrition imposed. The level of nutrition did not influence fat depots when the comparison was made at the same carcass weight. Ram lambs had less subcutaneous fat than did wethers, the difference increasing (P = 0.06) at heavier carcass weights (1 00 v. 20 1 g increase in subcutaneous fat/kg increase in carcass weight, for rams and wethers respectively). A similar trend was evident in GR tissue depth; consequently, the distribution of fat scores of wether carcasses was closer to the high (fat) end of the range than was the distribution for ram carcasses (P < 0.05). The levels of total solvent-extractable fat in the carcass did not differ between sexes or levels of nutrition.

scholarly journals Growth of atmospheric clusters involving cluster–cluster collisions: comparison of different growth rate methods

2016 ◽  
Vol 16 (9) ◽  
pp. 5545-5560 ◽  
Author(s):  
Jenni Kontkanen ◽  
Tinja Olenius ◽  
Katrianne Lehtipalo ◽  
Hanna Vehkamäki ◽  
Markku Kulmala ◽  
...  
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Particle Formation ◽  
Vapor Condensation ◽  
Model Substance ◽  
External Conditions ◽  
The Common ◽  
The Difference ◽  
Atmospheric Clusters ◽  
True Values

Abstract. We simulated the time evolution of atmospheric cluster concentrations in a one-component system where not only do clusters grow by condensation of monomers, but cluster–cluster collisions also significantly contribute to the growth of the clusters. Our aim was to investigate the consistency of the growth rates of sub-3 nm clusters determined with different methods and the validity of the common approach to use them to estimate particle formation rates. We compared the growth rate corresponding to particle fluxes (FGR), the growth rate derived from the appearance times of clusters (AGR), and the growth rate calculated based on irreversible vapor condensation (CGR). We found that the relation between the different growth rates depends strongly on the external conditions and the properties of the model substance. The difference between the different growth rates was typically highest at the smallest, sub-2 nm sizes. FGR was generally lower than AGR and CGR; at the smallest sizes the difference was often very large, while at sizes larger than 2 nm the growth rates were closer to each other. AGR and CGR were in most cases close to each other at all sizes. The difference between the growth rates was generally lower in conditions where cluster concentrations were high, and evaporation and other losses were thus less significant. Furthermore, our results show that the conventional method used to determine particle formation rates from growth rates may give estimates far from the true values. Thus, care must be taken not only in how the growth rate is determined but also in how it is applied.

scholarly journals A procedure to evaluate the effect of lag-time in studying length structure and growth rate of young fish: the case of Phycis blennoides Brunnich, 1768 (Osteichthyes: Gadiformes) in the Central Mediterranean

2002 ◽  
Vol 66 (S2) ◽  
pp. 253 ◽  
Author(s):  
Sergio Ragonese ◽  
Fabio Fiorentino ◽  
Paola Rinelli ◽  
Silvestro Greco
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Lag Time ◽  
Tyrrhenian Sea ◽  
Capture Process ◽  
Good Opportunity ◽  
Strait Of Sicily ◽  
Southern Tyrrhenian Sea ◽  
The Difference ◽  
Exploratory Procedure

The joint analysis of data from different programs represents a good opportunity to improve knowledge about the condition of any exploited populations. This note investigates the influence of lag-time in sample characteristics (growth rate and recruitment) by following a simple and quick exploratory procedure. In order to illustrate this approach, the Greater Fork-beard (Phycis blennoides Brunnich, 1768), a species with discrete recruitment pattern and available to the capture process in the first years of life, was considered . The length-frequency distributions (LFD), obtained during five spring (MEDITS - International) and successive autumn (GRUND - Italian) bottom trawl surveys, conducted from 1994 to 1998, in the Strait of Sicily and Southern Tyrrhenian Sea (Mediterranean) were analysed. The procedure was divided into three steps. Firstly, the LFD were analysed in order to estimate the mean length of the first component in each survey. Secondly, for each survey, the difference between the standardized mean lengths of the first components in the LFD of the two areas was compared with the corresponding lag-time in order to assess any systematic temporal effect in recruitment periodicity. Thirdly, for each area, the absolute and instantaneous growth rates between the spring and autumn surveys of the same year were computed on the base of the lag-time, to evaluate any difference in growth rate between the areas. The results show that the earlier the surveys begin in the Strait of Sicily, the smaller is the difference in mean length. Since the growth rates between the two areas are practically indistinguishable, the higher mean lengths observed in samples from the Strait of Sicily mainly reflect the lag-time. The reference mean growth rate found (1.03 and 0.93 cm per month in the Strait of Sicily and Southern Tyrrhenian Sea, respectively) agreed with the literature. In spring, the recruits of 0 group represent up to 90% of the whole trawl catch, and the smallest length class observed (4.5-5.0 cm) is close to the size of transition from the pelagic to the demersal one. The proposed exploratory procedure shows that systematic differences between the two investigated sub-areas in mean size and growth rate suggested by actual data are strongly reduced after having included the lag-time in the analysis.

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