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Ogacho, Alex; Aduda, Bernard O.; Nyongesa, F. W.

doi:10.1023/a:1023916009846

Cited by 9 publications

(8 citation statements)

References 15 publications

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“…Their utilization in heat transfer was much less frequent until now. Within the last couple of years, some references appeared on using the effective media theories for estimation of thermal conductivity of refractory materials [11], [12], syntactic foams [13], polymer-based composites [14] but not a single reference was found by the authors for cementitious composites, in common sources.…”

Section: Introductionmentioning

confidence: 99%

Effect of Moisture on the Thermal Conductivity of a Cementitious Composite

et al. 2006

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The measurements of thermal conductivity of a cement-based composite material are performed in dependence on moisture content from dry state to fully water saturated state using an impulse technique. Then, the obtained data are analyzed using Brugemann and Wiener homogenization formulas. The validity of applied homogenization techniques is assessed comparing the measured and calculated results. On the basis of the experimental data and the homogenization analyses, the effects of total pore volume, pore distribution and moisture content on the thermal conductivity are discussed. Key words:Thermal conductivity, moisture content, cementitious composites, homogenization IntroductionCementitious composites contain a significant amount of pores of different size. As the thermal conductivity of the air is 0.026 W/mK [1] and the thermal conductivity of cement stone is (depending on the amount and the type of aggregates) in the range of 1-3 W/mK [2], both the total pore volume and the distribution of pores can affect the thermal conductivity of a cementitious material in a very significant way. In usual service conditions, cementitious composites always contain certain amount of water. The thermal conductivity of water is 0.60 W/mK [1], which is more than 20 times higher than of the air. Therefore, if water is present in the pore space, its effect competes with the effect of air, and the thermal conductivity of a composite material can be considered as a result of this competition together with the effect of the cement matrix.

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Section: Introductionmentioning

confidence: 99%

Effect of Moisture on the Thermal Conductivity of a Cementitious Composite

et al. 2006

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“…Half of Rapoport's first prisoners were classified as invalids, useless as a labor force. 12 In violation of the security orders, Rapoport accepted hardened criminals and political prisoners. 13 According to Gulag regulations, dangerous criminals were to be guarded at all times, but Rapoport did not have enough guards.…”

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“…They lived in garrisons that were interchangeable with Gulag camps. 16 The military construction brigades consisted of soldiers considered too untrustworthy to bear arms. Many of the soldier-construction workers at the plutonium plant were veterans repatriated from Axis POW camps.…”

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confidence: 99%

“…Indigenous communities of Bashkir and Tatar farmers had been ordered out of the regime zone. 28 Select, majority-nation plutonium workers had moved into Cheliabinsk-40, where they were fenced in, guarded, and well-supplied. Residents had to carry a pass with them and could not leave the zone without special permission, which was granted to few for the first eight years of operation.…”

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confidence: 99%

“…In the cleansed buffer zone surrounding the regime zone, state collective farm villages of mostly Tatars and Bashkirs supplied Cheliabinsk-40 with farm produce and they also suffered the regular attacks and burglary of roving soldiers and prisoners foraging for food. 29 Despite Tkachenko's efforts in 1947, the job of cleansing the regime zone was still incomplete. In 1948, Beria again ordered that political undesirables be cleansed from the cadres of working prisoners.…”

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Securing the nuclear nation

Brown

2015

Natl. pap.

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In 1946, in the Southern Urals, construction of the Union of Soviet Socialist Republics first plutonium plant fell to the GULAG-Narodnyi Komissariat Vnutrennikh Del (NKVD). The chief officers in charge of the program -Lavrentii Beria, Sergei Kruglov, and Ivan Tkachenko -had been pivotal figures in the deportation and political and ethnic cleansing of territories retaken from Axis forces during WWII. These men were charged with building a nuclear weapons complex to defend the Soviet Union from the American nuclear monopoly. In part thanks to the criminalization and deportation of ethnic minorities, Gulag territories grew crowded with foreign nationals and ethnic minorities in the postwar years. The NKVD generals were appalled to find that masses of forced laborers employed at the plutonium construction site were members of enemy nations. Beria issued orders to cleanse the ranks of foreign enemies, but construction managers could not spare a single healthy body as they raced to complete their deadlines. To solve this problem, they created two zones: an interior, affluent zone for plutonium workers made up almost exclusively of Russians; and anterior zones of prisoners, soldiers, ex-cons, and local farmers, many of whom were non-Russian. The selective quality of Soviet "nuclearity" meant that many people who were exposed to the plant's secret plutonium disasters were ethnic minorities, people whose exposures went unrecorded or under-recorded because of their invisibility and low social value.In 1947, Narodnyi Komissariat Vnutrennikh Del (NKVD) generals broke ground on a new kind of Soviet city, a gated community in the southern Urals for specially selected workers dedicated to making plutonium for atomic bombs. Surrounded by a double-walled fence, topped by razor wire and patrolled by guards, Base Ten, later known as Cheliabinsk-40, then Cheliabinsk-65, and today called Ozersk, was one of the first and the largest closed nuclear cities in the Soviet Union. It serves as an interesting case study to determine how Soviet security officials correlated nationality with national security. It comes as no surprise that NKVD and later Ministerstvo Vnutrennikh Del (MVD) generals equated Russian and sometimes Ukrainian ethnicity with loyalty, while implicitly mistrusting citizens who had identities that could connect them with nations outside the Union of Soviet Socialist Republics (USSR). This kind of fear of cross-border alliances has been well documented (Iwanow

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