焦炭反射率与强度指标及反应性之间的相关性

通过控制偏光显微镜的起偏镜旋转角度可以实现焦炭气孔壁平均最大反射率Rˉmax和平均双反射率Rˉbi的自动测定。经回归分析发现,Rˉmax和焦炭反应性CRI,以及反应后强度CSR之间存在显著的相关关系,相关系数r分别达到－0.926和0.949。Rˉmax和焦炭机械强度DI 15015之间的相关性相对较弱,r为0.704。Rˉbi和焦炭各强度指标之间没有发现明显的相关关系。     

Coke Reactivity under Blast Furnace Conditions and in the CSR/CRI Test

The present work aims to study the high‐temperature strength of coke. Mechanisms of disintegration were evaluated using basket samples charged into LKAB's experimental blast furnace prior to quenching and dissection. Coke charged into basket samples was analysed with CSR/CRI tests and compared with treated coke from the blast furnace. Results from tumbling tests, chemical analyses of coarse and fine material, as well as light optical microscopy studies of original and treated coke have been combined and evaluated. The results indicate a correlation between the ash composition and the CSR values. Differences in the texture of the coke were noted with light optical microscopy, and a significant change in the coke texture during the CSR/CRI test conditions was found. The results suggest that the main reaction between coke and CO₂ took place in isotropic areas, which was especially pronounced in coke with a low CSR. Signs of degradation were apparent throughout the coke pieces that have undergone CSR/CRI testing, but were less observable in coke reacted in the blast furnace. The results indicate that reaction with CO₂ is generally limited by the chemical reaction rate in the CSR/CRI test, while in the blast furnace the reaction is limited by the diffusion rate. Coke degradation is therefore mostly restricted to the coke surface in the blast furnace.     

2000m3高炉焦炭质量评价

 由于目前还没有一个能综合反映焦炭质量的指标,因此从影响高炉焦比的角度出发,选取了焦炭灰分、硫分,以及M40,M10,CRI,CSR这6个指标并赋予不同的权重对焦炭质量进行评价。从焦炭质量指标、高炉技术经济指标和统计观点阐述了2000m3高炉用焦炭质量的评价方法。首次提出焦炭评分制,并建立了焦炭质量评价模型。同时加入焦炭预估价格、价格差和性价比等参数辅助评价焦炭质量。通过对8种焦炭进行模型验证,结果显示各焦炭质量差异明显,通过对高炉各焦炭配比进行优化之后,炉况运行稳定,焦炭成本降低。     

The development of hyperventilation in patients with chronic heart failure and Cheyne-Strokes respiration: a possible role of chronic hypoxia

AIM: To analyze the relationship between daytime respiratory and cardiac function in patients with compensated chronic heart failure (CHF) with and without periodic breathing (PB) or Cheyne-Stokes respiration (CSR). PATIENTS: We studied 132 patients (female, 13%; mean age, 53+/-8 years; body mass index, 25.9+/-3.5 kg/m2; left ventricular ejection fraction <40%; 23% in New York Heart Association class I, 43% in class II, and 34% in class III-IV). METHODS: Measurement of pulmonary function and blood gases, hemodynamic evaluation, analysis of breathing profile, echocardiography, recording of ECG, beat-to-beat arterial oxygen saturation, and respiration during spontaneous breathing. RESULTS: Fifty-eight percent of patients showed PB or CSR. Patients with PB or CSR have greater cardiac function impairment. Mean values of lung volumes and PaO2 were similar in the three groups of patients considered. In contrast, patients with PB or CSR had an increased minute ventilation and reduced PaCO2 values. Interestingly, patients with PB or CSR had lower values of arterial content of O2 and systemic oxygen transport (SOT) than patients with a normal breathing pattern (SOT, 394+/-9.8, 347+/-9.6, 438+/-11 mL of O2/min/m2, respectively; analysis of variance p<0.001). Weak correlations were found among lung volumes, blood gases, and cardiac function parameters: ie, vital capacity was correlated inversely with pulmonary capillary wedge pressure (PCWP) (-0.25; p<0.05); PaCO2 with PCWP (r=0.26; p<0.05), lung-to-ear circulation time (LECT) (r=-0.4; p<0.05), SOT (r=-0.33; p<0.0001), and cardiac index (CI) (r=0.27; p=0.003). Multiple regression analyses showed that arterial PCO2 was significantly correlated with SOT, LECT, and CI (r=0.51; r2=0.26; p<0.000001); the correlation became stronger considering only CSR patients (r=0.64; r2=0.4; p<0.001). CONCLUSIONS: Our study shows that patients with daytime breathing disorders have chronic hypocapnia. A reduced SOT may be one of the stimuli determining increased minute ventilation in these patients.     

宝钢焦炭强度预测和配煤煤质控制

在总结国内外炼焦配煤控制方法的基础上,确定了宝钢焦炭强度预测和配煤煤质控制方法的基本思想,构筑了一种新的预测焦炭强度的参数ＣＣＩ。根据试验获得的数据,采用多元逐步回归进行了焦炭强度的预测,宝钢焦炉焦炭的ＤＩ１５＾１５０、ＣＲＩ和ＣＳ折预测值与实测值有关很好的相关关系。     

焦炭热态性能对高炉产质量影响的统计解析

 焦炭是高炉重要的燃料之一。 为研究不同范围内焦炭热态性能对高炉产质量指标的影响，首先统计实际高炉生产数据，将焦炭热态性能划分为不同区间，利用SPSS软件对不同区间数据进行统计解析，通过线性或非线性拟合得出影响规律和适宜的反应性和反应后强度。鉴于反应性和反应后强度存在较强的负相关性，综合考虑两因素，得出合适的焦炭综合热态性能，从而指导高炉和炼焦生产并提供一种新的焦炭热态性能研究方法。     

Intratumoral blood flow in uterine myoma correlated with a lower tumor size and volume, but not correlated with cell proliferation or angiogenesis

OBJECTIVE: To investigate the correlation of intratumoral blood flow in uterine myoma with cell proliferation, angiogenesis, tumor size, and tumor volume. METHODS: Thirty-nine patients who had been scheduled for surgery because of symptomatic uterine myomas were evaluated by transvaginal sonography and color Doppler ultrasound before surgery. The largest dimension of each tumor and the volumes of myomas were determined ultrasonographically. Pulsatility index (PI) was determined by color Doppler ultrasound according to the maximum systolic, end-diastolic, and the mean flow velocities measured within the uterine nodules. After surgery, the paraffin-embedded slides containing representative leiomyoma tissues were stained with hematoxylin and eosin, proliferating cell nuclear antigen for measurement of cell proliferation, and factor VIII for quantitation of microvessel density. The ultrasonographic findings were correlated postoperatively with pathologic findings, and the data were analyzed by simple linear regression and Fisher r to z transformation. RESULTS: Simple regression analysis of the intratumoral PI values on the sizes of myomas showed a negative correlation (r = -0.47, P = .003; n = 39), whereas a less significant correlation between PI values and tumor volumes was observed (r = -0.42, P = .008). In contrast, no statistically significant correlation was observed between the intratumoral PI values and the values of the proliferating cell nuclear antigen index (r = 0.10, P = .547) or microvessel density counts (r = 0.18, P = .282). CONCLUSION: The intratumoral blood flow by transvaginal color Doppler ultrasound correlated with a reduced tumor size and tumor volume, but did not correlate with cell proliferation or angiogenesis.     

灰成分对焦炭热性能的影响

通过在配煤中分别加入不同量的Fe2O3、CaO、MgO、K2O、Na2O、SiO2、Al2O3、P2O5、TiO2改变灰成分的炼焦试验，和大量的模拟生产配煤的炼焦试验。获得169组试验数据，采用回归分析的方法获得了宝钢煤源条件下，焦炭灰成分中十大主要成分对焦炭热性能影响的次序。确立了适合宝钢煤源条件的灰催化指数ACI计算方法。建立了焦炭灰成分对焦炭热性能影响的数学模型。     

宝钢控制焦炭热性质的研究

根据19种单种煤和64个配煤方案在模拟焦炉（SCO）上的试验，研究了原料煤性质对焦炭热性质的影响，并在此基础上建立了控制宝钢焦炭热性质的模型，实践表明，该模型能很好地预测焦炭热性质，预测值与实绩值误差，CRI＜3％，CSR＜4％，指导宝钢炼焦配煤生产。     

溶损反应前后焦炭反射率及光学组织的比较

 为了解焦炭中各显微光学组织在溶损反应中的反应行为，对不同条件下溶损反应前后焦炭的反射率及显微光学组织组成进行了分析。试验表明，焦炭的反射率指标及光学组织组成与焦炭的反应性CRI、反应后强度CSR之间存在比较好的相关性。焦炭的平均最大反射率[Rmax]和光学各向异性指数Φ越高，各向同性光学组织越少，其CRI越低，CSR越高。经过1 100 ℃溶损反应后，焦炭的[Rmax]提高，各向同性光学组织含量减少，各向异性光学组织含量增加，说明各向同性的反应性高于各向异性。溶损反应温度提高到1 300 ℃以后，焦炭中各向同性的溶损反应量分别为1 100 ℃时的1.07～3.00倍，而各向异性的溶损反应量分别为1 100 ℃的1.22～8.58倍，且热性能越好的焦炭各向异性反应量增加得越多。     

Serum intact parathyroid hormone and ionised calcium concentration in children with renal insufficiency

We report our experience of the use of an immunoradiometric assay for intact parathyroid hormone (i-PTH) and the measurement of plasma ionised calcium concentration (PCa2+) in 73 children with chronic renal insufficiency (CRI); plasma creatinine concentration (PCr) 52-856 mumol/l. There was a poor correlation between i-PTH and PCr (r = 0.10, n = 552) compared with that for C-terminal PTH and PCr (r = 0.60, n = 248), suggesting that the i-PTH assay is independent of renal function in this group of treated children. A clear response of i-PTH to a low total plasma Ca (tPCa) and PCa2+ was observed. There was a significant positive correlation between both tPCa and PCa2+ (r = 0.50, n = 389) and the fraction of Ca2+ (the fraction of tCa which was ionised) and PCa2+ (r = 0.50, n = 389). The finding of a low or normal PCa2+ with a low calculated fraction of Ca2+ was frequently observed, i.e. the measured tPCa was unexpectedly high, suggesting complexing of Ca2+ by accumulated anions in CRI. There was a poor relationship between the plasma albumin concentration and both bound plus complexed Ca (tPCa minus PCa2+) and the fraction of Ca2+ (r = 0.15 and -0.17, respectively). The positive predictive value for a raised i-PTH of a tubular reabsorption of phosphate of less than 80% was 0.87, and of an alkaline phosphatase greater than 800 U/l was 0.37.(ABSTRACT TRUNCATED AT 250 WORDS)     

Correlation between echocardiographic changes and parameters of pulmonary function in patients with arterial hypertension

This study comprised 30 patients with mild or moderate arterial hypertension (according to classification of the World Health Organization) in whom some echocardiogram and parameters of the lung function were studied in order to establish correlation between them. A good correlation exists between LV (left ventricle) mass index and vital capacity (r = 0.562, p < 0.01), ejection fraction and forced mid expiratory flow (r = 0.717, p < 0.01), LV mass index and Tiffenau index (r = 0.620, p < 0.01), shortening fraction and forced mid expiratory flow (r = 0.591, p < 0.01), airways resistance and posterior wall thickness (r = 0.591), p < 0.01) and between LV mass index and total lung capacity (r = 0.821, p < 0.01). There was not a good correlation or it was not significant (p > 0.05) between other echocardiographic changes and lung function tests.     

高喷煤比操作对焦炭劣化的影响

为考查提高喷煤量对焦炭在炉内劣化的影响，在宝钢高炉上进行了风口取样研究。结果表明，喷煤量达到200kg/t以上时焦炭劣化严重。高炉生产实绩回归显示，焦炭的热性能对高炉透气性的影响比冷强度显著。分析认为焦炭热性能指标CRI、CSR对高炉高煤比操作更重要。借此还提出了提高喷煤量和改善焦炭质量需加强研究的课题。     

结焦时间对冶金焦热态性能的影响

焦炭的质量主要取决于配合煤质量和炼焦操作。配合煤质量和炼焦加热温度对焦炭质量的影响已有详尽论述，但结焦时间对焦炭质量的影响还没有深入的研究。塔塔钢厂的实验表明．焖炉可提高焦炭的平均尺寸和焦炭结构的致密性。焦炭经重大的结构变化．使其各向同性结构减少．粗粒和细粒镶嵌结构的数量增加。孔径减小。随着结焦时间的延长，焦炭的热态性能。即焦炭反应性（CRI）和反应后强度（CSR），均得到提高。     

Near-infrared estimation of O2 supply and consumption in forearm muscles working at varying intensity

We estimated a blood flow index, O2 supply index, and O2 consumption index from near-infrared (NIR) signals during venous occlusion imposed at rest and immediately after handgrip exercise with loads equal to 5, 10, 15, 20, 25, and 30% of the maximum voluntary contraction. We also estimated forearm blood flow (BFfa) by strain-gauge plethysmography and forearm O2 consumption (VO2fa) by the invasive method. There was a significant correlation between the rate of increase in total hemoglobin during venous occlusion obtained from NIR signals and BFfa in each subject (r = 0.853 approximately 0.981, P < 0.001). There was also a significant correlation (r = 0.854 approximately 0.944, P < 0.001) between the O2 consumption index estimated from NIR signals and VO2fa. The mean values for O2 supply index in five subjects increased with exercise intensity, while the O2 consumption index showed no further increase about 25% of maximum voluntary contraction. We found significant positive correlations between the O2 supply index and BFfa (r = 0.986, P < 0.001) and the O2 consumption index and VO2fa (r = 0.976, P < 0.001) during exercise at 5-30% of maximum voluntary contraction. These results demonstrate that analysis of NIR signals during venous occlusion provides an advantageous method of estimation of O2 supply and consumption in working muscles during exercise of varying intensity.     

焦炭溶损对高炉冶炼的影响和焦炭高温性能讨论

分析了焦炭反应性CRI和反应后强度CSR指标相差很大的焦炭在国内外高炉能够使用的原因。通过焦炭溶损反应对高炉还原、热交换和焦炭溶损劣化的作用分析,提出了一些焦炭热性质及其质量指标,供高炉操作和炼焦配煤参考。     

新型含硼季铵盐对焦炭热态性能的改善研究

 以含硼季铵盐（N-甲基溴代十二烷基二乙醇胺硼酸酯）作为新型焦炭劣化抑制剂,考察其对焦炭的热态性能改善影响,并对焦炭结构和形貌进行表征,初步探讨了含硼季铵盐改善焦炭热态性能的机理。结果表明：喷洒含硼季铵盐溶液后焦炭热态性能指标得到明显改善,1.0%的含硼季铵盐能使焦炭反应性CRI降低8.69%,反应后强度CSR提高7.94%,焦炭表面积、气孔直径和深度显著减小,减弱了二氧化碳对焦炭的侵蚀劣化作用,这为改善焦炭性能指标开拓了新途径。     

Kidney function and age are both predictors of pharmacokinetics of metformin

The effects of renal impairment and age on the pharmacokinetics of metformin were evaluated. The subjects, including 6 young, 12 elderly, and 3 middle-age healthy adults and 15 adults with various degrees of chronic renal impairment (CRI) each were given a single, 850-mg metformin HCl tablet. Multiple whole blood, plasma, and urine samples were collected and analyzed for metformin levels using a high-performance liquid chromatography (HPLC) method. In healthy elderly individuals, the plasma and whole blood clearance/absolute bioavailability values [CL/F and (CL/F)b], and corresponding renal clearance values (CLR and CLR,b) of metformin were 35-40% lower than the respective values in healthy young individuals. These two groups did not differ significantly with respect to volume of distribution (Vd), time to peak concentration (tmax), and parameters related to metformin's appearance in the urine. In the moderate and severe CRI groups, all clearance values were 74-78% lower than in the healthy young/middle-age group, and all other evaluable pharmacokinetic parameters (with the exception of tmax) differed significantly in this group. In the mild CRI group, clearance values of metformin, which were 23-33% lower than in the young/middle-age group, were the only parameters that differed significantly. Based on a regression analysis of the combined data, both creatinine clearance (CL*cr; corrected for body surface area) and age are predictors of metformin clearance, with the following model best fitting the data: CL/F [or (CL/F)b, CLR, CLR,b] = alpha + beta.CL*cr + gamma.CL*cr.age. Metformin should not be used in patients with moderate and severe CRI, or in patients with mild, but not absolutely stable, renal impairment. The initial and maximum doses in elderly patients and patients with stable mild CRI should be lowered to approximately one third that given to the general (i.e., patients without non-insulin-dependent diabetes) population.     

干熄焦焦炭质量特性研究

采用微观和宏观技术手段研究了焦炭质量特性,分析了在6m焦炉140t/h的条件下干熄焦与湿熄焦的质量差异。试验结果显示,干熄焦和湿熄焦相比,灰分略有升高,抗碎强度M40提高,耐磨强度M10降低,焦炭反应性CRI降低,而焦炭反应后强度CSR提高。干熄焦和湿熄焦之间灰成分无明显差异,干熄焦焦炭的气孔率比湿熄焦低,干熄焦焦炭的显微结构各项异性指数OTI提高。研究表明,气孔率和焦炭显微结构的变化是焦炭冷热强度变化的内在原因,其中焦炭气孔率变化达到8.8％,是引起焦炭反应后强度变化的主要原因。     

Nutrition and bone mineral density in premenopausal women

Environmental factors have an important role in osteoporosis. Diet and, in particular, nutrients like calcium, vitamin D or phosphorus were extensively studied as determinants of bone mineral density, but the results remain conflicting and there is no clear evidence for an independent effect of such factors in the bone density of premenopausal women. We studied 66 healthy premenopausal women (20-40 years-old) aiming to relate bone mineral density, as measured in three different sites (distal forearm, lumbar spine and femoral neck) using single X ray and dual energy X-ray absorptiometry, with nutritional intake as estimated by a semi-quantitative food frequency questionnaire. Demographic, anthropometric and other life style variables were also assessed. There was a significant correlation between distal forearm and femoral neck (r = 0.57) or lumbar spine (r = 0.45) bone mineral density. No significant effect of age was observed for distal forearm bone mineral density in these women. In a stepwise multiple linear regression model, evaluating the contribution of all the variables studied, only body mass index (p=0.038) and vitamin A ingestion (p = 0.020) had an independent contribution for the variation in distal forearm bone mineral density. Mean bone mineral density, assessed in the femoral neck (p = 0.003) or the lumbar spine (p = 0.056) was different across tertiles of alcohol ingestion, being higher in non-drinkers. However, among regular drinkers there was a significant positive correlation between alcohol ingestion and femoral neck bone mineral density (Spearman's r = 0.53, p = 0.015). This study shows that the effect of nutrition seems dependent on the anatomical site assessed and that there is a weak correlation between nutritional intake and the actual bone mineral density.