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Energy consumption is an important factor in the operation of machine tools. Recent studies showed that in average, 1 / 5 of the machine tools total energy demand is caused by internal cooling systems. The continually rising performance of machine tools, together with the importance of thermal stability, reasons the requirement for demand oriented cooling approaches, which could significantly reduce the energy consumption for internal machine cooling. This study applied classic and demand oriented cooling strategies on a machine tool frame, which is one of the most complex machine tool components from a thermal point of view. The demand oriented cooling is based on volume flow control and can either be configured close to the environmental temperature or close to the thermal steady state, which can be obtained by loss forecast in combination with an FE model or measurement. The impact of the strategies on the thermal reaction as well as the energy consumption is compared, showing a significant reduction of energy demand without significant impairment of the thermal stability. [ABSTRACT FROM AUTHOR]

The paper considers stresses emerging in the skin of a continuously cast steel billet, as well as their values under the influence of temperature expansions in a novel patented design of a nickel mold with a two-circuit cooling system. According to the known values of heat flux densities at various distances from the top of the mold, the temperature of the slag-forming mixture and the average temperature of the steel billet skin are determined. Based on the established thickness of the billet skin, the temperature gradient therein is determined. At a steel casting speed of 4 m/min, the values of temperature stresses in the billet skin at various distances from the top of the mold were established not to exceed the values of the metal flow stresses at corresponding temperatures. [ABSTRACT FROM AUTHOR]

Ambient temperature control and active internal cooling can effectively reduce the impact of spindle thermal error. At the same time, the residual spindle thermal error fluctuates violently, which makes it difficult to predict the thermal error accurately. To combat this issue, experiments to identify the spindle thermal error with constant and variable spindle speed spectrums were designed. A deep learning model is proposed for thermal error prediction, wherein speed parameter is incorporated as an input variable alongside temperature variables. The proposed model adopts a 1D convolutional neural network-gated recurrent unit-attention (1DCNN-GRU-Attention) architecture. Within this model, the 1DCNN module is responsible for managing the highly collinear input data and extracting spatial information, followed by the GRU module which extracts temporal information. Furthermore, the attention mechanism of the model can re-weight the learned features. Ultimately, the regression layer is responsible for predicting thermal error. To verify the proposed model's effectiveness, it was compared against seven other thermal error prediction models. The experimental results revealed that the convolutional module of the proposed model is highly effective and can replace the traditional temperature-sensitive point selection (TPS) method. Under multiple coupled factors, the proposed method achieved a prediction accuracy of 81.53%, with root-mean-square error (RMSE) lower than the traditional method by 40%. [ABSTRACT FROM AUTHOR]

Purpose: Foot sole cooling increases vestibular-evoked balance responses, but less is known about foot dorsum temperature alterations. The purpose was to determine whether decreasing cutaneous receptor sensitivity via foot dorsum cooling modulates the vestibular control of balance. Methods: Eighteen participants (9 males; 9 females) stood quietly on a force plate with feet together, eyes closed, and head rotated leftward during 4, 90-s trials (2 control; 2 cooled) of continuous electrical vestibular stimulation (EVS). Icepacks placed on the dorsum of both feet for 15 min induced cooling and remained throughout the EVS trials. Monofilament testing was performed at multiple locations before and after cooling to determine tactile detection thresholds. T-type thermocouples monitored skin temperature over the tibialis anterior, soleus, foot dorsum and arch of the right leg. Vestibular-evoked balance responses were characterized using time (cumulant density) and frequency (coherence and gain) domain analyses to determine the relationship between the EVS input and motor output (anteroposterior force—AP force; right medial gastrocnemius electromyography—MG EMG). Results: Skin temperature of the foot dorsum and arch decreased ~ 70 and 15%, respectively during cooling (p < 0.05), but was unaltered at other locations (p ≥ 0.10). Detection thresholds for the foot dorsum increased following cooling (p < 0.05). Surprisingly, cooling reduced EVS-AP force and EVS-MG EMG coherence and gain at multiple frequencies, and peak-to-peak amplitude compared to control (p < 0.05). Conclusion: Our results indicate that vestibular-driven balance responses are reduced following foot dorsum cooling, likely owing to alterations in cutaneous mechanoreceptor sensitivity and subsequent alterations in the transformation of vestibular cues for balance control. [ABSTRACT FROM AUTHOR]

The electric-field-enhanced effect of permittivity is one of the most important physical properties of KTa1-xNbxO3 in paraelectric, thus greatly affecting the performance of electro-optic modulator and deflector. We studied the temperature dependence of the electric-field-enhanced effect and the effect of supercooling on it. We found that this enhanced effect is closely related to the Fröhlich entropy, with a minimum value that corresponds to the strongest field enhancement effect. We further discovered that supercooling could improve the field-enhanced effect by 15%, because of the small polar nanoregion (PNR) size and high polarization. In addition, we propose a novel model to describe the electric-field-enhanced characteristic of the permittivity. The model can well explain the enhanced permittivity under DC electric field and reveal that the field enhancement of permittivity is mainly caused by reorientation of PNRs gradually activated by the DC electric field. [ABSTRACT FROM AUTHOR]

A vessel containing a classical non-relativistic ideal gas is studied, which has a small hole. Gas effuses through this hole, but the hole is so tiny that the gas inside the vessel remains homogeneous. The density and the temperature of the gas inside the vessel are obtained as functions of time. [ABSTRACT FROM AUTHOR]

The famous Kissinger's kinetic evaluation method (Anal Chem 29:1702, 1957) is examined with respect to the feasible impact of the individual quantities and assumptions involved. It is accentuated that the missing term on heat inertia may change the resulting values when searching for activation energies. Particular attention is paid to the heating rate, β, particularly when applied under opposite process of cooling. In such case of melt solidification, an additional thermodynamic term for the melt undercooling is needed to be incorporated which provides an alternative form of evaluation. Despite as many as 8000 applications caused by the obvious methods simplicity, these affects was overlooked. It is surprising that anybody who evolved various alternatives of the Kissinger method did not find any reasons for its criticism. [ABSTRACT FROM AUTHOR]

Solid-state cooling based on caloric effects is considered a viable alternative to replace the conventional vapor-compression refrigeration systems. Regarding barocaloric materials, recent results show that elastomers are promising candidates for cooling applications around room-temperature. In the present paper, we report supergiant barocaloric effects observed in acetoxy silicone rubber—a very popular, low-cost and environmentally friendly elastomer. Huge values of adiabatic temperature change and reversible isothermal entropy change were obtained upon moderate applied pressures and relatively low strains. These huge barocaloric changes are associated both to the polymer chain rearrangements induced by confined compression and to the first-order structural transition. The results are comparable to the best barocaloric materials reported so far, opening encouraging prospects for the application of elastomers in near future solid-state cooling devices. [ABSTRACT FROM AUTHOR]

Purpose: This study investigated whether muscle cooling and its associated effects on skeletal muscle oxidative responses, blood gases, and hormonal concentrations influenced energy metabolism during cycling. Methods: Twelve healthy participants (Males: seven; Females: five) performed two steady-state exercise sessions at 70% of ventilatory threshold on a cycle ergometer. Participants completed one session with pre-exercise leg cooling until muscle temperature (Tm) decreased by 6 °C (LCO), and a separate session without cooling (CON). They exercised until Tm returned to baseline and for an additional 30 min. Cardiovascular, respiratory, metabolic, hemodynamic variables, and skeletal muscle tissue oxidative responses were assessed continuously. Venous blood samples were collected to assess blood gases, and hormones. Results: Heart rate, stroke volume, and cardiac output all increased across time but were not different between conditions. V̇O2 was greater in LCO when muscle temperature was restored until the end of exercise (p < 0.05). Cycling in the LCO condition induced lower oxygen availability, tissue oxygenation, blood pH, sO2%, and pO2 (p < 0.05). Insulin concentrations were also higher in LCO vs. CON (p < 0.05). Importantly, stoichiometric equations from respiratory gases indicated no differences in fat and CHO oxidation between conditions. Conclusion: The present study demonstrated that despite muscle cooling and the associated oxidative and biochemical changes, energy metabolism remained unaltered during cycling. Whether lower local and systemic oxygen availability is counteracted via a cold-induced activation of lipid metabolism pathways needs to be further investigated. [ABSTRACT FROM AUTHOR]

Possibilities of increasing the efficiency of technology for production of 8–16 (25) mm thick strip in strip mills having different consumer demand for hot-rolled sheet are demonstrated. Such production methods as redistribution of reductions in the roughing group stands, installation of induced cooling and heat protection screens on the intermediate roller table, rolling sheet of variable thickness ("wedgeshaped") in the finishing group of stands, make it possible to control temperature effectively both over strip length and thickness without use of external heat sources, and without loss of continuous hot rolling high productivity. [ABSTRACT FROM AUTHOR]

The authors propose a technique for predicting the conditions for the appearance of thermal fatigue cracks on the surface of rotating continuous rollers of slab continuous-casting machines (CCMs) based on the asymptotic analysis of the problem of thermoelasticity on planar deformation. The technique enables to estimate tension, displacements, and deformations in the surface layer of rollers considering the magnitude and nature of the thermal load, and the angular velocity of rotation. It can serve as the basis for choosing the material for the production of rollers, the conditions for their cooling, and the rhythm of casting. The effectiveness and justification of the proposed method are confirmed by an experiment. [ABSTRACT FROM AUTHOR]

An experimental study was performed of the influence of mixing intensifier-grids on the cooling of a 37-rod electrically heated TVS-2M model with top and bottom reflooding. It is shown that the mixing grids bring about a very small reduction of the maximum temperature of the rods and longer cooling time of the assembly. To cool the TVS-2M model, the starting temperature of the fuel-rod simulators and the power input can be significantly lower in top reflooding than in bottom reflooding. The effect of the flooding rate is similar to that observed in bottom flooding – as the flooding rate increases, the maximum temperature of the rods and the cooling time of the assembly decrease. The experiments showed that with reflooding the mixing grids do not greatly affect the cooling efficiency of TVS-2M. [ABSTRACT FROM AUTHOR]

In this study, a simple methodology is proposed to estimate ambient temperature bin data. The proposed model is based on the determination of the best fitting equation describing the characteristics of the cumulative frequency distribution of yearly bin weather data values. This approach makes it easy for anyone, who needs bin data values for any location, to adopt the fitted equations in the building energy performance calculations. A case study was applied to six cities in Turkey, and the applicability of the proposed model has been shown. The obtained R2 values of the fitted equations are higher than 0.99. Therefore, the coefficients of the fitted equations for any location can be used easily to predict any bin data value to be used in building energy performance calculations. The results of this study are important for the experts using bin method. [ABSTRACT FROM AUTHOR]

Purpose: Cooling sensations elicited by mouth rinsing with L-menthol have been reported as ergogenic. Presently, responses to L-menthol mouth rinsing during intermittent sprint performance (ISP) in the heat are unknown and the impact of increased thermal perception on ISP via capsaicin has also not been quantified. This experiment aimed to identify whether eliciting cooling/warming sensations via L-menthol/capsaicin would alter ISP in the heat.Method: Fourteen participants (mass = 72 ± 9 kg, [Formula: see text] = 3.30 ± 0.90 L min-1), undertook four experimental trials, involving 40 min of ISP in hot conditions (40.2 ± 0.6 °C, 42 ± 2% R.H.) with mouth rinsing (25 mL, 6 s) at the protocol onset, and every 10 min thereafter. Cooling (0.01% L-menthol; MEN), warming (0.2% capsaicin; CAP), placebo (0.3 sham-CHO; PLA), and control (water; CON) mouth rinses were utilized. Performance was quantified via power (PP) and work done (WD) during sprints. Heart rate (HR), core (Trec) and skin (Tskin) temperature, perceived exertion (RPE), thermal sensation (Tsens), and comfort (Tcom) were measured at 10 min intervals. Sweat rate (whole-body sweat rate) was calculated from ∆mass.Result: PP reduced over time (P < 0.05); however, no change was observed between trials for PP or WD (P > 0.05). Tcom increased over time and was lower in MEN (2.7 ± 1.1; P < 0.05) with no difference between CAP (3.1 ± 1.2), PLA (3.2 ± 1.3) and CON (3.1 ± 1.3). RPE, Tsens HR, Trec, and Tskin increased over time (P < 0.05) with no between trial differences (P > 0.05).Conclusion: Despite improved thermal comfort via L-menthol, ISP did not improve. Capsaicin did not alter thermal perception or ISP. The reduction in ISP over time in hot conditions is not influenced by thermal perception. [ABSTRACT FROM AUTHOR]

The effect of silicon on the transformations of austenite under cooling, the content of silicon and carbon in the austenite, the conditions of precipitation of structurally free carbon in the form of globular graphite, and the formation of microstructure in chromium-nickel iron is studied for attaining a high level of mechanical properties in cast condition. [ABSTRACT FROM AUTHOR]

The oil at high temperatures in the reservoir loses heat to the surroundings and is submitted to different shear stresses while it is produced and transported. Thermal and shear histories have great influence on the rheological characteristics of waxy oils at low temperature. Wax crystals precipitate during cooling, building up a percolated matrix that entraps the oil and consequently, forms a gel-like structure. One of the main parameters that affect the crystals’ morphology and therefore the gel strength is the cooling rate. Although the oil static cooling has been widely studied in the literature, many questions are still open. The current work analyzes the influence of the cooling rate on the gel strength and on the dynamic moduli (G′ and G″) of a waxy model oil. Microscopic images of wax crystals were obtained and a hypothesis to explain the non-monotonic response of the rheological parameters as a function of the cooling rate is proposed based on the crystals’ morphology. [ABSTRACT FROM AUTHOR]

High grinding temperature restricts the machining efficiency and precision of some aeronautical difficult-to-machine materials. Aiming to enhance heat exchange with the grinding zone and reduce grinding temperature, heat pipe grinding wheel (HPGW) provides a novel method through improving the thermal conductivity of grinding wheel assisted by heat pipe. In this paper, the structure of HPGW is introduced and the workpiece temperature and energy partition in wet grinding using HPGW based on a wheel-fluid composite surface model is analyzed. Wet grinding experiments including creep feed grinding, high-speed shallow grinding and high-efficiency deep grinding (HEDG) are carried to investigate the cooling characteristics of HPGW according to the workpieces of titanium alloy Ti-6A1-6 V and Inconel 718. Compared with using the traditional grinding wheel, the results show that using HPGW in creep feed grinding and HEDG can maintain a lower grinding temperature and avoid the burnout under a relatively high removal rate, but cooling effect of HPGW is not obviously different from the traditional grinding wheel in high-speed shallow grinding due to a small heat input at the evaporator of HPGW. [ABSTRACT FROM AUTHOR]

The investigation was aimed at evaluation of level and rate of cutaneous and tympanic temperature drop due to a single short-timed (3 min) cooling in a cryosauna (–70°С), and adaptation-indicative physiological parameters, including blood catecholamines, ACTH, lipoproteins and free fatty acids. The subjects were seven healthy men. Exposure to cold invariably reduced the internal (tympanic) and cutaneous temperature by 1°С and 7°С on average, respectively. Tympanic temperature remained 0.4°С low on the average for more than 20 min after exposure. Cutaneous temperature was 1°С below the norm for an hour after cooling. For one hour after the short-term cold exposure, blood norepinephrine remained increased, and so did the blood concentrations of high-density lipoprotein cholesterol and free fatty acids. These results demonstrate brief adaptive changes following a single exposure at –70°C. [ABSTRACT FROM AUTHOR]

The results of joint analysis of temperature variations near mesopause from long-term measurements at the Zvenigorod Scientific Station of the Obukhov Institute of Atmospheric Physics RAS in 1960-2015 and variations of surface air temperature characterizing global climate change. Together with variations of temperature at the mesopause T from measurements of the hydroxyl emissions we analyzed the temperature variations near mesopause T reduced to the same level of solar activity. The observed strong decrease in temperature near mesopause during last decades, particularly in winter, with its tendency to slow down since the 1980's is was detected against the background of general increase in the surface air temperature of the Northern Hemisphere T and the Earth as a whole. It was revealed a sharp drop in winter temperature near mesopause in 1970s. and its synchronicity with the shift in climatic features at the surface associated with changes in formation of El Nino events and their impact on the global climate. The general significant negative correlation of temperature variations near mesopause and T detected from 56-year observational data was not accompanied by any significant coherence between the most long-period temperature variations from the cross-wavelet analysis. To assess the possible manifestation of this coherence the results of numerical simulations with a global climate model were used. According to model simulations for the 20-21 centuries taking into account anthropogenic forcings for significant coherence between long-term variations T and T the prolonged observations are required for temperature near mesopause-about a century or more. [ABSTRACT FROM AUTHOR]

Analysis of the thermo-mechanical performance of high-frequency vacuum electron devices is essential to the advancement of RF sources towards high-power generation. Operation in an ultra-high vacuum environment, space restricting magnetic focusing, and limited material options are just some of the constraints that complicate thermal management in a high-power VED. An analytical method for evaluating temperature, stress, and deformation distribution in thin vacuum-to-cooling walls is presented, accounting for anisotropic material properties. Thin plate geometry is used and analytical expressions are developed for thermo-mechanical analysis that includes the microstructure effects of grain orientations. The method presented evaluates the maximum allowable heat flux that can be used to establish the power-handling limitation of high-frequency VEDs prior to full-scale design, accelerating time-to-manufacture. [ABSTRACT FROM AUTHOR]

This work presents the study of the characteristic retention times on Carbosieve SIII adsorbent for several permanent gases CO, CO, CH, N with respect to the temperature of cooling of adsorption accumulators. To perform this work, a laboratory model of a gas chromatograph that included all key components of a standard instrument has been designed. [ABSTRACT FROM AUTHOR]

Underwater friction stir welding is an alternative method to improve the mechanical properties of the weldments by controlling the temperature level. Owing to the limitation of temperature measurement in practice, the finite element modeling is the best tool to investigate the process. It is still not clearly known as to what extent the temperature field of joint is influenced by operational parameters in underwater friction stir welding. In this paper, finite element modeling of friction stir welding in the air and underwater were performed for Al6061-T6 alloys to control the thermal cycles. In addition to cooling effect, the influence of welding speed and rotational speed on the maximum temperature in workpiece was investigated. For this purpose, three-dimensional modeling has been done with ANSYS. The model results were then examined by experimental data, and a reasonable agreement was observed. It is found that due to water cooling effect, heat is dissipated in faster rate which leads to low peak temperature in underwater welding compared to normal welding in air, while such relationship was not seen in high welding speeds. The reason is that at high welding speeds, workpiece temperature decreases, and region of boiling water in underwater welding is reduced. This causes that heat will be dissipated from workpiece surface in faster rate. Tool rotational speed has significant effect on thermal cycles than welding speed. Moreover, in normal friction stir welding, the peak temperature diminishes with respect to welding speed in faster manner in comparison with welding in underwater. [ABSTRACT FROM AUTHOR]

In some cases, in the Netherlands, an additional layer is being added to the thermocouple, used to measure the rectal temperature in medicolegal death investigations. Because of this deviation from the standard method, questions arose regarding the accuracy and precision of the measured temperature. Therefore, a cooling experiment was carried out on a round body made of agar with an average thermal conductivity of 0.454 W/(m °C) while measuring the temperature with and without an additional layer around the thermocouple for three different starting temperatures: 36, 30, and 27 °C. The results show a significant difference between the measured values for the first 5 min when comparing with and without the additional layer. Further, a decrease in precision is present within the first minutes when using an additional layer. Therefore, it is concluded that it is best to measure the rectal temperature without an additional layer around the thermocouple and caution should be taken when measuring with an additional layer. [ABSTRACT FROM AUTHOR]

Acne treatment by a mid-infrared laser may be unsatisfactory due to deeply situated acne-affected sebaceous glands which serve as its target. Skin manipulation by vacuum and contact cooling may improve laser-skin interaction, reduce pain sensation, and increase overall safety and efficacy. To evaluate the safety and efficacy of acne treatment using an integrated cooling-vacuum-assisted 1540-nm erbium:glass laser, a prospective interventional study was conducted. It included 12 patients (seven men and five women) suffering from mild-to-moderate acne vulgaris. The device utilizes a mid-infrared 1540-nm laser (Alma Lasers Ltd. Caesarea, Israel), which is integrated with combined cooling-vacuum-assisted technology. An acne lesion is initially manipulated upon contact by a vacuum-cooling-assisted tip, followed by three to four stacked laser pulses (500-600 mJ, 4 mm spot size, and frequency of 2 Hz). Patients underwent four to six treatment sessions with a 2-week interval and were followed-up 1 and 3 months after the last treatment. Clinical photographs were taken by high-resolution digital camera before and after treatment. Clinical evaluation was performed by two independent dermatologists, and results were graded on a scale of 0 (exacerbation) to 4 (76-100 % improvement). Patients' and physicians' satisfaction was also recorded. Pain perception and adverse effects were evaluated as well. All patients demonstrated a moderate to significant improvement (average score of 3.6 and 2.0 within 1 and 3 months, respectively, following last treatment session). No side effects, besides a transient erythema, were observed. Cooling-vacuum-assisted 1540-nm laser is safe and effective for the treatment of acne vulgaris. [ABSTRACT FROM AUTHOR]

A procedure for the evaluation of the thermal conditions for the rolls of continuous casting machines operating in the conditions of scale formation in the cooling channel is proposed. The procedure allows a differentiated approach to the determination of the axisymmetric and maximum surface temperature of the rolls with allowance for the magnitude and behavior of the thermal load and the cooling and scale formation conditions on the heat-exchange surfaces. It can be used to predict the roll service life and to rate the quality of cooling water. [ABSTRACT FROM AUTHOR]

This article presents a three-dimensional mathematical (dynamic) model of the sintering process. The model was developed to solve theoretical and practical problems. It allows real-time determination of the distributions of the temperatures and the chemical compositions of the charge, the melt, the sinter cake, and the gas in the bed of charge materials with allowance for transients. The model also permits real-time determination of the temperatures in the pallets and the parameters of the gas flow (including infiltrating air) in the flue system of the sintering machine. [ABSTRACT FROM AUTHOR]

A three-dimensional mathematical (dynamic) model is presented to describe the sintering process. The model was developed to solve theoretical and practical problems. It allows real-time determination of the dynamic distribution of the temperature and chemical composition of the charge, the melt, the sinter cake, and the gas in the bed with allowance for transients, as well as the temperatures in the pallets and the parameters of the gas flow in the flue channel - including air infiltration. [ABSTRACT FROM AUTHOR]

A domestically produced device for determining the cooling capacity of quenchants is developed on the basis of the ISO 9001, ISO 9950, ASTM D6200-01, and ASTM D6482-01 standards. Acomparison of the results of a determination of the parameters of cooling environments obtained by means of the present device and a foreign counterpart is carried out. [ABSTRACT FROM AUTHOR]

This summer study evaluated the effect of providing additional fans (cooling) in the resting area within a free-stall dairy barn that had fans and sprinklers in the feeding area and paddock availability. Thirty cows were divided into two homogenous groups and kept in two pens: one had the resting area equipped with two fans (FAN) while no fans were added to the other resting area (CON). Microclimatic parameters, rectal temperature (RT), breathing rate (BR), milk yield, and milk pH traits were recorded. Time budgeting and the behaviour of the cows (time spent in the feeding area, standing and lying in other areas) were also recorded using digital video technology. Two slight-to-moderate heat waves were observed. During the hottest period the daily maximum temperature recorded was 33.5 °C and the daily maximum THI was 81.6. During this period, the BR and RT increased only slightly in both groups, with lower BR (n.s.) in FAN compared with CON. Milk yield was better maintained (n.s.) in FAN compared with CON during the hottest period. The FAN cows showed a greater ( P < 0.05) lying time in the free stalls (9.5 and 8.6 h/day in FAN and CON, respectively), whereas CON cows made greater ( P < 0.05) use of the paddock during evening and late evening hours. Consequently, the total daily lying time was 13.5 h/day in both groups. In conclusion, the results suggest that using fans in the resting area improves cow comfort, which increases use of the resting area. The lying time results also suggest that the benefits of providing ventilation in the resting area might be more evident in barns where there is no paddock. [ABSTRACT FROM AUTHOR]

The effect of heating condition for continuously-cast slabs of different cross section on the probability of corner crack formation is analyzed. Versions are considered for correction of cooling water and air flow rates in secondary cooling zone (SCZ) sprayers with the aim of optimizing the thermal profile of continuously-cast billets poured from crack-resistant steels. SCZ operating regimes are developed for the Azovstal Metallurgical Combine CBCM-6 making it possible to reduce the overall level of slab surface cleaning by 30%. [ABSTRACT FROM AUTHOR]

Despite the continued increase in atmospheric greenhouse gas concentrations, the annual-mean global temperature has not risen in the twenty-first century, challenging the prevailing view that anthropogenic forcing causes climate warming. Various mechanisms have been proposed for this hiatus in global warming, but their relative importance has not been quantified, hampering observational estimates of climate sensitivity. Here we show that accounting for recent cooling in the eastern equatorial Pacific reconciles climate simulations and observations. We present a novel method of uncovering mechanisms for global temperature change by prescribing, in addition to radiative forcing, the observed history of sea surface temperature over the central to eastern tropical Pacific in a climate model. Although the surface temperature prescription is limited to only 8.2% of the global surface, our model reproduces the annual-mean global temperature remarkably well with correlation coefficient r = 0.97 for 1970-2012 (which includes the current hiatus and a period of accelerated global warming). Moreover, our simulation captures major seasonal and regional characteristics of the hiatus, including the intensified Walker circulation, the winter cooling in northwestern North America and the prolonged drought in the southern USA. Our results show that the current hiatus is part of natural climate variability, tied specifically to a La-Niña-like decadal cooling. Although similar decadal hiatus events may occur in the future, the multi-decadal warming trend is very likely to continue with greenhouse gas increase. [ABSTRACT FROM AUTHOR]

A method of strength analysis with accounting of residual welding stresses (RWSs) is described. This consists in the calculation of such a field of initial temperatures from which upon cooling in a construction a corresponding field of residual stresses is obtained. The selected form of the representation of RWSs provides the possibility for their use during the simulation of the process of loading the welded construction by the finite element method. [ABSTRACT FROM AUTHOR]

This paper presents the first annually resolved temperature reconstruction for England in the Middle Ages. To effect this reconstruction the starting date of the grain harvest in Norfolk has been employed as a temperature proxy. Using c. 1,000 manorial accounts from Norfolk, 616 dates indicating the onset of the grain harvest were extracted for the period 1256 to 1431 and a composite Norfolk series was constructed. These data were then converted into a temperature series by calibrating a newly constructed comparison series of grain harvest dates in Norfolk from 1768 to 1816 with the Central England Temperature series. These results were verified over the period 1818-1867. For the British Isles no other annually resolved proxy data are available and the onset of the grain harvest remains the only proxy for assessing April-July mean temperatures. In addition, this is the first time-series regarding the onset of grain harvests in medieval Europe known so far. The long-term trend in the reconstructed medieval temperature series suggests that there was a cooling in the mean April-July temperatures over the period 1256 to 1431. Average temperatures dropped from 13°C to 12.4°C, which possibly indicates the onset of the Little Ice Age. The decline in values was not steady, however, and the reconstruction period contains decades of warmer spring-early summer temperatures (for example the 1320s to the early 1330s and the 1360s) as well as colder conditions (for example the late 1330s, 1340s and the 1380s). The decline in grain-growing-season average temperatures would not have been a major problem for medieval agriculture, rather the phases of very high interannual variability partly found in the medieval time-series, such as 1315-1335 and 1360-1375, would have proved disruptive. [ABSTRACT FROM AUTHOR]

Using published experimental data an expression was derived for the Ti/Ti ratio as a function of temperature, oxygen fugacity, and melt composition. The equation can be used to estimate Ti content in lunar basaltic melts. It was shown that the Ti content in melts is probably no higher than the Fe3+ content even under the reduced conditions typical of lunar magmas. Trivalent Ti can lead to some decrease in $$f_{O_2 }$$ during melt cooling under closed-system conditions, but it cannot reduce Fe in melt to metal, because it will be completely consumed by Fe reduction to Fe. The presence of additional reducers, such as Cr, can be favorable for the formation of metal during melt cooling. [ABSTRACT FROM AUTHOR]

This paper presents an experimental and analytical study on the inverter split-type air-conditioner for the purpose of energy saving and a proper balance between sensible and latent capacity. Performance of an inverter split-type air-conditioner is investigated at varied refrigerant mass flow rates, air volume flow rates, and set point temperatures. The performance investigated for a 2.54-kW inverter split-type air-conditioner includes cooling capacity, power consumption, the value of coefficient of performance (COP), and equipment sensible heat ratio (SHR). An increase of electrical frequency input to compressor from 34 to 66 Hz results in an increase of cooling capacity by 0.88 kW, a decrease of COP by 0.84, and a decrease of SHR by 0.11. An increase in cooling coil flow rate from 4.14 to 8.2 m3/min results in an increase in cooling capacity by 0.16 kW, an increase in COP by 0.10, and an increase in SHR by 0.15. An increase of set point temperature from 24 to 26°C results in an increase of the value of COP by 0.13 and a decrease of SHR by 0.03. The study offers guidelines for the application of small-size inverter split-type air-conditioners in hot and humid climates. [ABSTRACT FROM AUTHOR]

The durability and thermal stability of hardened Portland cement pastes containing vermiculite (V) and expanded vermiculite (EV) exposed to high temperatures were studied. Different mixtures were prepared using 2.5, 5, and 10 wt% of both types of V. Each mixture, after 28 days of hydration, was heated at 300, 600, and 800 °C for 3 h. Two modes of cooling were used; gradual cooling in air and rapid cooling in cold water. The percentage of residual strength, chemically combined water content, change in phase composition, and the thermal stability of the heated specimens were studied. The specimens cooled in water showed greater loss in strength than the air-cooled specimens. The presence of V improved the heat resistance of ordinary type I Portland cement (OPC) pastes. 5 wt% replacement revealed the best performance at all heating temperatures. The EV showed better thermal resistance than the nonexpanded one. Addition of silica fume (SF) with V in OPC pastes lead to superior performance. This can be explained as result of the combined effects of insulation properties of V and pozzolanic reactivity of SF which accounts for the notable increase in the residual strength for these mixes. [ABSTRACT FROM AUTHOR]

A three-dimensional (3-D) transient numerical analysis was performed inside an automobile cabin during cooling period. A three-dimensional vehicle cabin including glazing surfaces was modelled by using the real dimensions of a car. A virtual manikin with real dimensions and physiological shape was added to the model of the vehicle cabin, and it was assumed that the manikin surfaces were subjected to constant temperature. The virtual manikin was divided into 17 parts in standing posture to evaluate the local heat transfer characteristics of the human body during transient cooling period. We considered three different cases that the cooling capacity of the automobile cabin was same for all cases. Three-dimensional fluid flow, temperature distribution and heat transfer characteristics inside the automobile cabin were calculated with different type of inlet vents. Comparisons of the numerical results were presented and discussed. [ABSTRACT FROM AUTHOR]

The quality of an injection molded part is largely affected by the mold cooling. Consequently, this makes it necessary to optimize the mold cooling circuit when designing the part but prior to designing the mold. Various approaches of optimizing the mold cooling circuit have been proposed previously. In this work, optimization of the mold cooling circuit was automated by a commercial process integration and design optimization tool called Process Integration, Automation and Optimization (PIAnO), which is often used for large automotive parts such as bumpers and instrument panels. The cooling channels and baffle tubes were located on the offset profile equidistant from the part surface. The locations of the cooling channels and the baffle tubes were automatically generated and input into the mold cooling computer-aided engineering program, Autodesk Moldflow Insight 2010. The objective function was the deviation of the mold surface temperature from a given design temperature. Design variables in the optimization were the depths, distances and diameters of the cooling channels and the baffle tubes. For a more practical analysis, the pressure drop and temperature drop were considered the limited values. Optimization was performed using the progressive quadratic response surface method. The optimization resulted in a more uniform temperature distribution when compared to the initial design, and utilizing the proposed optimization method, a satisfactory solution could be made at a lower cost. [ABSTRACT FROM AUTHOR]

An experimental study of heat transfer characteristics of steam in a square channel (simulating a gas turbine blade cooling passage) with two opposite surfaces roughened by 60 deg parallel ribs was performed. The ranges of key governing parameters were: Reynolds numbers (Re) based on the channel hydraulic diameter (30000-140000), entry gauge pressure (0.2Mpa-0.5Mpa), heat flux of heat transfer surface area (5kWm-20kWm), and steam superheat (13°C-51°C). The test channel length was 1000mm, while the rib spacing (p/e) was 10, and the ratio of rib height (e) to hydraulic diameter (D) was 0.048. The test channel was heated by passing current through stainless steel walls instrumented with thermocouples. The local heat transfer coefficients on the ribbed wall from the channel entrance to the fully developed regions were measured. The semi-empirical correlation was fitted out by using the average Nusselt numbers in the fully developed region to cover the range of Reynolds number. The correlation can be used in the design of new generation of gas turbine blade cooled by steam. [ABSTRACT FROM AUTHOR]

For liquid Ti, it is difficult to achieve high undercooling because of its chemical reactivity; as a result, there is little information available on its properties and structure in the undercooled state. In this study, we investigate the density and structure, using molecular dynamics method, for the undercooling and superheating ranges 0-743 K and 0-457 K. The density increases quadratically for undercooling. At the melting temperature, the density is 4.14 g/cm, and first and second temperature coefficients are obtained. The pair correlation functions and coordination numbers indicate that the short range degree of order becomes increasingly significant with increasing undercooling. [ABSTRACT FROM AUTHOR]

We report on the controlled insertion of individual Cs atoms into an ultracold Rb gas at ≈400 nK. This requires one to combine the techniques necessary for cooling, trapping and manipulating single laser cooled atoms around the Doppler temperature with an experiment to produce ultracold degenerate quantum gases. In our approach, both systems are prepared in separated traps and then combined. Our results pave the way for coherent interaction between a quantum gas and a single or few neutral atoms of another species. [ABSTRACT FROM AUTHOR]

On the basis of use of a method of separation of variables and the orthogonal method of Bubnov-Galerkin, the exact analytical solution of the hyperbolic equation of heat conductivity for an infinite plate under boundary conditions of the first sort is obtained. It is shown that heating of the body (cooling) is deter-mined by movement of the thermal shock wave on which there is a temperature jump. The front of the thermal wave divides the investigated area into two subareas splitting where the temperature changes from the wall temperature (a boundary condition of the first sort) to the temperature at the front waves and not splitting when the temperature is equal to the reference temperature. [ABSTRACT FROM AUTHOR]

An experimental study on the heat transfer performance of microencapsulated phase change material suspensions flowing in the rectangular tube of small aspect ratio (b/a = 0.14) is presented in this work. The slurry of higher MPCM concentration shows better cooling performance in the most section of dimensionless axial distance whereas worse in a small section at the beginning. Up to 20.6% of the dimensionless wall temperature was decreased by the 20 wt% MPCM suspension as compared to water. [ABSTRACT FROM AUTHOR]

In situ Raman spectra of hydrous wadsleyite (β-MgSiO) with ~1.5 wt% HO, synthesized at 18 GPa and 1,400°C, have been measured in an externally heated diamond anvil cell up to 15.5 GPa and 673 K. With increasing pressure (at room temperature), the three most intense bands at ~549, 720 and 917 cm shift continuously to higher frequencies, while with increasing temperature at 14.5 GPa, these bands generally shift to lower frequencies. The temperature-induced frequency shifts at 14.5 GPa are significantly different from those at ambient pressure. Moreover, two new bands at ~714 and ~550 cm become progressively significant above 333 and 553 K, respectively, and disappear upon cooling to room temperature. No corresponding Raman modes of these two new bands were reported for wadsleyite at ambient conditions, and they are thus probably related to thermally activated processes (vibration modes) at high-pressure and temperature conditions. [ABSTRACT FROM AUTHOR]

The formation of hydrogels from diacylphosphatidylcholine (PC) and water/glycerol mixtures and the properties of the gels are reported. The gels are formed when L phases from the PC in the solvent mixtures are cooled from T >55 °C below the Krafft temperature of the PC ( T ∼52 °C). The glycerol can also be replaced by other co-solvents like butylenglycol. Above T, the PC spontaneously forms L phases with multilamellar vesicles that show a strong stationary birefringence. On cooling below T, the L phases jellify to transparent gels. DSC measurements of the gels show that the PC molecules undergo a phase transition into the crystalline state. This transition does not seem to be accompanied by a change of the morphological structure of the liquid L phase. The hydrogels also have a stationary birefringence. The vesicles in the gels have been imaged by the CryoTEM method. The hydrogels are already formed with as little as 1% of PC in the mixed solvent. The rheological properties of the gels were determined from oscillating rheological measurements. Samples with 10% of PC have a storage modulus of >10,000 Pa. [ABSTRACT FROM AUTHOR]

The inherent irreversibility and thermal stability in a long hollow cylinder with temperature-dependent internal heating and asymmetric convective cooling at both inner and outer surfaces is investigated. Analytical solution is obtained for the governing equation and the expressions for the temperature field, thermal stability criterion, volumetric entropy generation number, and irreversibility distribution ratio are presented. With certain combinations of the heat transfer parameters, entropy generation rates can be minimized. [ABSTRACT FROM AUTHOR]

Hot-strip mills (HSMs) continue to occupy the leading position in the production of hot-rolled strip. One remaining bottleneck in HSM lines is the intermediate roller conveyor, where the slab being rolled undergoes significant (nonuniform in the length direction) cooling. Passive methods of shielding the metal are widely used on continuous HSMs to slow the metal's cooling. In recent years, data have appeared on active methods of regulating the thermal state of the slab on the conveyor: continuous tunnel furnaces and pseudo-active shields. This article analyzes the thermal and energy efficiency of these methods of maintaining slab temperature. It is shown that a continuous tunnel furnace solves this problem with a very low energy efficiency. [ABSTRACT FROM AUTHOR]

An electronic literature search through August 2010 was performed to obtain articles describing fever incidence, impact, and treatment in patients with subarachnoid hemorrhage. A total of 24 original research studies evaluating fever in SAH were identified, with studies evaluating fever and outcome, temperature control strategies, and shivering. Fever during acute hospitalization for subarachnoid hemorrhage was consistently linked with worsened outcome and increased mortality. Antipyretic medications, surface cooling, and intravascular cooling may all reduce temperatures in patients with subarachnoid hemorrhage; however, benefits from cooling may be offset by negative consequences from shivering. [ABSTRACT FROM AUTHOR]

This paper presents an approach for generating a well-defined cooling pattern over an area of tissue. An array of solid-state microcoolers is used, which could be included in a probe that provides local cooling. This medical instrument can be used for removal of scar tissue in the eye or for the rapid stopping of bleeding due to micro-cuts, which makes it a useful tool to medical doctors and could make surgery more secure to the patient. The array of microcoolers is composed of 64 independent thermo-electric elements, each controlled using an integrated circuit designed in CMOS. The independent control allows the flexible programming of the surface temperature profile. This type of control is very suitable in case abrupt temperature steps should be avoided. Cooling by lateral heat flow was selected in order to minimize the influence of heat by dissipation from the electronic circuits. Moreover, a thermo-electric component with lateral heat allows fabrication of the cooling elements using planar thin-film technology, lithography and wet etching on top of the silicon wafer. This approach is potentially CMOS compatible, which would allow for the fabrication of the thermo-electric elements on top of a pre-fabricated CMOS wafer as a post-process step. Each pixel is composed of thin-films of n-type bismuth telluride, BiTe and p-type antimony telluride, SbTe, which are electrically interconnected as thermocouple. These materials have excellent thermoelectric characteristics, such as thermoelectric figures-of-merit, ZT, at room temperatures of 0.84 and 0.5, respectively, which is equivalent to power-factors, PF, of 3.62 × 10 W Km and 2.81 × 10 W Km, respectively. The theoretical study presented here demonstrates a cooling capability of 15°C at room temperature (300 K ≈ 27°C). This cooling performance is sufficient to maintain a local tissue temperature at 25°C, which makes it suitable for the intended application. A first prototype was successfully fabricated to demonstrate the concept. [ABSTRACT FROM AUTHOR]

The inception process of nucleation in explosive boiling systems is theoretically investigated. With the effect of pulse heating or sudden cooling, the temperature distribution near the surface during explosive boiling is calculated. The liquid near the wall can maintain a stable layer induced by strong attractive force, and there exists maximum supersaturation beyond this stable layer. As the surface temperature and temperature gradient are high enough, the critical distance of maximum supersaturation can be larger than the radius of critical bubble, and the homogeneous nucleation will dominate the inception boiling process. For explosive boiling induced by pulse heating, homogeneous nucleation forms after a short time; while homogeneous nucleation can dominate the initial explosive boiling induced by sudden cooling. [ABSTRACT FROM AUTHOR]