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Background Positive youth development theory can provide an alternative approach to promote Seat Belt Use while Riding in a Car (SBURC) among youth. The study aims to explore the relationship between youth assets, and the neighborhood environment in predicting SBURC. Methods The Youth Asset Study (YAS) is a 4-year (5 waves) longitudinal study of a random sample of 1,111 youth (12-17 years old) and their parents, taking place in a Midwestern city, USA from 2003-2008. Seventeen youth assets were developed. The environment was measured objectively via the broken windows survey and subjectively via parents’ interviews. Assets and environmental factors at Waves 1-4 predicted SBURC at Waves 4-5 while controlling for demographics. Data were analyzed via marginal logistic regression and generalized estimated equations analyses. Results The sample consisted of 1001 youth: 53% female; mean age=14.36 (SD = 1.59); 50% with income Conclusions Youth assets can be an alternative approach to promote SBURC among teens with emphasis on promoting parental monitoring, responsible choices, general aspirations for the future, and good health practices. Key messages • Building youth assets can be another mechanism to promote seat belt use while driving among youth. • The neighborhood environment might not be as important as other factors are in the promotion of seat belt use while driving.

Background Positive youth development theory can provide an alternative approach to promote Seat Belt Use while Driving in a Car (SBUDC) among youth. The study aims to explore the relationship between youth assets, and the neighborhood environment in predicting SBUDC. Methods The Youth Asset Study (YAS) is a 4-year (5 waves) longitudinal study of a random sample of 1,111 youth (12-17 years old) and their parents, taking place in a Midwestern city, USA from 2003-2008. Seventeen youth assets were developed. The environment was measured objectively via the broken windows survey and subjectively via parents’ interviews. Assets and environmental factors at Waves 1-4 were predicted SBUDC at Waves 4-5 while controlling for demographics. Data were analyzed via marginal logistic regression and generalized estimated equations analyses. Results The sample consisted of 1001 youth: 53% female; mean age=14.36 (SD = 1.59); 50% with income Conclusions Youth assets can be a promising approach to promote SBUDC among teens with emphasis on promoting general aspirations for the future, educational aspirations, and positive peer role modeling. Key messages • Building youth assets can be another mechanism to promote seat belt use while driving among youth. • The neighborhood environment might not be as important as other factors are in the promotion of seat belt use while driving.

Chamberprotection of metals from atmospheric corrosion is a variety of vapor-phase inhibition. It is based on the effect of adsorption films formed in the vapors of low-volatile corrosion inhibitors at elevated temperatures. The paper analyzes the specific features of the chamber protection of a magnesium alloy with chlorobenzotriazole. It has been found that the protective properties of surface films formed in hot vapors of this compound increase upon exposure of the metal to air. The processes of structuring of protective films that occur in this case have been studied by a set of corrosion, electrochemical and physical methods. It has been shown that chamber treatment of the alloy is accompanied by chlorobenzotriazole adsorption and uniform thickening of the surface oxide-hydroxide layer. In this case, the corrosion processes slow down by a factor of up to 10. Prolonged exposure of the samples in air after the chamber treatment results in additional oxidation of magnesium and hydroxylation of the oxide. However, the oxide-hydroxide layer does not grow on the entire surface, but as separate islets. Such a change in the structure of the surface films results in an additional 10-fold increase in the corrosion resistance of the magnesium alloy.

Chamber protection is a promising and quickly developing method of vapor-phase protection of metals against atmospheric corrosion by inhibitors. It was shown that chamber treatment with 2-ethylhexanoic acid (EHA) efficiently inhibits the initiation of zinc corrosion. The optimum conditions (temperature and duration) of zinc treatment with vapors of this compound were determined. If these conditions are met, adsorption films of EHA with thicknesses up to 100 nm are formed on the metal surface. It was found that their protective properties increase during the first day as zinc is exposed to air after chamber treatment. The anticorrosive action of adsorption films is due both to the surface being shielded from the corrosive environment and to the inhibition of corrosion processes on the active surface of the metal. Corrosion inhibition was caused by the ability of EHA to convert zinc to the passive state and inhibit its local anionic depassivation.

It has been shown by a set of corrosion, electrochemical and physical methods that a chamber corrosion inhibitor that consists of a mixture of octadecylamine (ODA) and benzotriazole (BTA) efficiently protects copper and brass from atmospheric corrosion and can be used for the temporary protection of metal items. The optimum temperatures of treatment with the ODA + BTA mixed inhibitor is 120 °C for brass and 100 °C for copper. One-hour treatment in ODA + BTA vapors at these temperatures results in the formation of nanosized adsorption films on the surface of these metals. These films stabilize the passive state and provide efficient temporary protection of metal items. The ODA + BTA inhibitor is superior to its components in terms of protective aftereffect. Our analysis of the mutual effect of BTA and ODA indicated that they show an antagonism of protective action on copper, but there is also a synergistic enhancement in the case of brass. Electrochemical impedance spectroscopy studies demonstrate that the inhibitors in question mainly act by using a blocking mechanism on copper and brass. Chamber treatment of the metals studied in vapors of the ODA + BTA mixture resulted in a noticeable hydrophobization of the copper surface and an insignificant effect on the brass surface. Chamber treatment of copper samples with artificially created polymodal roughness made it possible to obtain a superhydrophobic surface.

BACKGROUND: The role of isoforms of prostate specific antigen (PSA) and other kallikrein-related markers in early detection of biochemical recurrence (BCR) after radical prostatectomy (RP) is not well known and serum PSA is currently used in preoperative risk nomograms. OBJECTIVE: The aim of this research was to study pre- and early postoperative levels of important PSA isoforms and human kallikrein-2 to determine their ability to predict BCR and identify disease persistence (DP). METHODS: This study included 128 consecutive patients who underwent RP for clinically localized prostate cancer. PSA, fPSA, %fPSA, [–2]proPSA, PHI and hK2 were measured preoperatively, at 1 and 3 months after RP. We determined the ability of these markers to predict BCR and identify DP. RESULTS: The DP and BCR rate were 11.7%and 20.3%respectively and the median follow up was 64 months (range 3–76 months). Preoperatively, the independent predictors of BCR were PSA (p-value 0.029), [–2]proPSA (p-value 0.002) and PHI (p-value 0.0003). Post-RP, PSA was the single marker correlating with BCR, both at one (p-value 0.0047) and 3 months (p-value 0.0004). PSA, fPSA, [–2]proPSA and PHI significantly correlated to DP at 1 and 3 months post-RP (p-value < 0.05), although PSA had the most significant existing correlation (p-value < 0.0001). CONCLUSIONS: [–2]proPSA and PHI are preoperative predictors of BCR and DP that outperform the currently used serum PSA. At the early postoperative period there is no additional benefit of the other markers tested.

Objectives Renal cell carcinoma (RCC) is the most lethal urologic malignancy with increasing incidence worldwide. The conventional treatment strategies for advanced or recurrent RCC are not efficient and show considerable toxicities. Adoptive cell transfer (ACT) has become a promising treatment option for multiple cancers, particularly in combination with other therapeutic approaches. ACT often utilizes extensively in vitro expanded tumor-infiltrating lymphocytes (TILs). However, TILs are a very heterogeneous mix of cell populations and only those populations that have a cytotoxic and migratory potential are thought to deliver a therapeutic impact in ACT. The identification and localization of these therapeutically potent populations are therefore needed. Methods and materials A total number of 57 tissue samples from 19 RCC patients who underwent radical nephrectomy was analyzed. The tissue samples were obtained from the tumor, peritumoral tissue, and the adjacent healthy renal tissue. The tissues were sliced, enzymatically dissociated into single cell suspensions and the obtained cells further analyzed by flow cytometry for the expression of markers of lymphocyte cytotoxicity – TRAIL and FasL, and a surrogate marker of lymphocyte migratory activity – PECAM-1. The analyzed data were next correlated with the clinical and histopathological data. Results Non-clear cell RCC (non-ccRCC) tumors showed a significantly decreased tumor infiltration with TRAIL+FasL+ NK cells but elevated infiltration with FasL+PECAM-1+ T cells as compared with clear cell RCC (ccRCC) tumors. Further analyses revealed that the peritumoral tissue of ccRCC patients is a reservoir of TRAIL+FasL+, TRAIL+PECAM-1+, or FasL+PECAM-1+ NK and T cells. Conclusions The cytotoxic/migratory lymphocytes were identified in tumors of ccRCC patients. These lymphocytes became excluded from the tumor and accumulated in the patient's peritumoral tissue.

Background We aimed to explore the utility of prostate specific antigen (PSA) isoform [− 2] proPSA and its derivatives for prediction of pathological outcome after radical prostatectomy (RP). Methods Preoperative blood samples were prospectively and consecutivelyanalyzed from 472 patients treated with RP for clinically localized prostate cancerat four medical centers. Measured parameters were PSA, free PSA (fPSA), fPSA/PSA ratio, [− 2] proPSA (p2PSA), p2PSA/fPSA ratio and Prostate Health Index (PHI)(p2PSA/fPSA)*√PSA]. Logistic regression models were fitted to determine the accuracy of markers for prediction of pathological Gleason score (GS) ≥7, Gleason score upgrading, extracapsular extension of the tumor (pT3) and the presence of positive surgical margin (PSM). The accuracy of predictive models was compared using area under the receiver operating curve (AUC). Results Of 472 patients undergoing RP, 339 (72%) were found to have pathologic GS ≥ 7, out of them 178 (53%) experienced an upgrade from their preoperative GS = 6. The findings of pT3 and PSM were present in 132 (28%) and 133 (28%) cases, respectively. At univariable analysis of all the preoperative parameters, PHI was the most accurate predictor of pathological GS ≥7 (OR 1.02, 95% CI 1.01–1.03, ppppAUC = 66.6 (p = 0.015) and GS upgrading by 5.0% to AUC = 65.9 (p = 0.025), respectively. Conclusions Preoperative PHI levels may contribute significantly to prediction of prostate cancer aggressiveness and expansion of the tumor detected at final pathology.

Purpose: Prostate-specific antigen (PSA) is a sensitive but unspecific marker for prostate cancer (PC) detection, which may result in harms including overdiagnosis and overtreatment. Therefore, the development of new markers is of absolute value. The urinary level of engrailed-2 (EN2) protein has been recently suggested as a promising PC biomarker, correlating with tumour volume and stage. This study evaluated EN2 and its potential use in clinical practice.Materials and methods: Urinary EN2 was assessed by different commercially available enzyme-linked immunosorbent assay kits. The study sample included 90 patients with clinically localized PC compared to 30 healthy controls, and a group of 40 patients indicated for prostate biopsy due to an elevated PSA level where both pre- and post-digital rectal examination urine samples were collected.Results: No statistical difference between the patient group and the control group was obtained in all measured variables. There was no significant correlation between urinary EN2 and serum PSA, tumour staging and grading. Attentive DRE did not lead to significant changes of urinary EN2 or impact on its predictive power.Conclusions: Our results show that EN2 as a PC biomarker brings no additional value to the current use of PSA in clinical practice.

The aim of this study was to construct a stratification model based on early postoperative kinetics of prostate-specific antigen (PSA) to select the most suitable high-risk patients for early intervention after radical prostatectomy (RP).The study evaluated 205 men who had undergone RP without any adjuvant treatment. All of the patients had positive surgical margins, extracapsular extension and/or seminal vesicle invasion. The patients underwent multiple ultrasensitive PSA measurements on days 14, 30, 60 and 90 after RP, and subsequently at 3 month intervals. The ability of particular PSA measurements to predict biochemical recurrence (BCR) was assessed using the area under the curve (AUC). A sequential mathematical decision procedure was constructed to create a stratification model.During the median follow-up of 45.9 months, 106 patients (51%) experienced BCR. Prediction of BCR in terms of the AUC for PSA measurements on days 14, 30, 60 and 90 after the surgery was 0.61, 0.70, 0.80 and 0.82, respectively. In the multivariate analysis, only PSA after RP remained as a predictor of progression-free survival (p 0.001). The stratification model based on calculated cut-off values for PSA on day 30 (0.068 ng/ml) and PSA on day 60 (0.015 ng/ml) reduced the potential overtreatment rate by 37%.The results imply that ultrasensitive PSA values obtained very early after RP correlate with the presence of recurrent disease in high-risk patients. Incorporating these readily available variables into risk stratification models may help to individualize the administration of adjuvant radiotherapy and thus to minimize overtreatment.

The central purpose of this article is to explore research, issues, and perspectives on the implementation of service learning programs to improve student achievement in at-risk student populations. The implementation of service learning programs takes place within multiple contexts and across several terrains. The complexities of implementing service learning are captured in a framework of “contextual dynamism” which consists of six interrelated terrains: the political, the economic, the accountability, the financial, the demographic, and the staffing. In this article, the authors explore each of the terrains, ending with recommendations for policymakers and practitioners.

The electrochemical behavior of copper and zinc in neutral (рН 7.4) borate buffer solution with addition of 0.5 M NaCl and the effect of 2-merсaptobenzothiazole (MBT) on the electrochemical processes and adsorption on these metals has been studied by means of electrochemistry and X-ray photoelectron spectroscopy (XPS). The formation of MBT– metal cation complex films on copper and zinc surface has been shown. The effect of corrosive media composition and time-dependent relations of nanoscale film growth on the surface of the metals investigated have been determined. It was assumed that adsorbed MBT anion forms M(MBT)х, a polymeric complex where M = Cu + (x = 1) or Zn 2+ (x = 2).

Contemporary tools estimating increased risk of prostate cancer (PCa) relapse after radical prostatectomy (RP) are far from perfect and there has been an intensive search for additional predictive variables. We aimed to explore whether the parameters of postoperative ultrasensitive prostate-specific antigen (PSA) decline provide additional information for predicting PCa progression.A total of 319 consecutive men, with at least 2 years of follow-up after RP for clinically localized PCa were subjected to this study. Intensive postoperative measurements of ultrasensitive PSA resulted in total of 4028 PSA values available for statistical evaluation. Biochemical recurrence (BCR) was defined as PSA ≥0.2 ng/ml. The accuracy of predictive models was quantified with the area under the curve.Over a median follow-up of 43 months (24-99 months), 107 patients (34%) experienced BCR after RP. In patients with BCR, significantly higher values of PSA nadir (p0.001) and a decreased time interval from surgery to reach PSA nadir (p0.001) were observed. A multivariable Cox regression model confirmed that PSA nadir0.01 ng/ml (HR 6.01, 95% CI: 3.89-9.52) and time to PSA nadir3 months (HR 2.86, 95% CI: 1.74-5.01) were independent predictors of BCR. The inclusion of PSA nadir and the time to PSA nadir into the model resulted in improvement of predictive accuracy by 16% over the model designed on the basis of established parameters.Our results demonstrate that the level of PSA nadir and the time to PSA nadir determined by ultrasensitive assay significantly improve the identification of patients who are at high risk of disease recurrence after RP.

Background: It has been shown that expression and activity of lysosomal proteolytic enzymes (i.e., cathepsin B) correlate with tumor progression in various neoplasms. We investigate possible correlation of cathepsin B concentrations with grading and invasivity of tumorous bladder tissue. Method: Cathepsin B concentrations in serum and urine were measured in 40 patients (29 men, 11 women, mean age 68 years) with transitional cell carcinoma (TCC) of the bladder without metastases and in control group of 64 healthy subjects (28 men, 36 women, mean age 55 years) using commercially available enzymatic immunoassay. Concentration of cathepsin B in urine was adjusted on creatinine. Urinary creatinine in all samples was measured by enzymatic creatinase method. Patients were divided into groups according to the grading (low grading: 18 patients

Presented exploratory pilot study was aimed at evaluation of proteins present in urinary specimens collected from prostate cancer suffering subjects after radical prostatectomy, divided into two experimental cohorts: positive (n=15) and negative (n=15) surgical margins (PSM/NSM). The presence of PSM suggests inadequate cancer clearance and the possible need for additional treatment. Proper identification of these risk-patients is therefore of a paramount importance. Total protein profiles were firstly identified by using SDS-PAGE and compared by using partial least square discrimination analysis (PLS-DA), which revealed differences in molecular weights of 80-99 and 150-235 kDa between the experimental groups. For further identification of proteins, comparative proteomic technologies were employed. Two-dimensional gel electrophoresis with subsequent identification of protein spots by using MALDI-TOF mass fingerprinting revealed differential expression of proteins between NSM/PSM cohorts. Moreover, in PSM group, three uniquely identified proteins (cyclin-dependent kinase 6, galectin-3-binding protein and L-lactate dehydrogenase C chain) were found, which show tight connection with prostate cancer and presence of all of them was previously linked to certain aspects of prostate cancer. These proteins may be associated with the molecular mechanisms of prostate cancer development; hence, their identification may be helpful for the assessment of disease progression risk after radical prostatectomy, but also for possible early diagnosis.

Traditionally, local school districts have shouldered the burden of funding school infrastructure in the name of local control, relying upon local prop erty tax revenues and the willingness of local voters to approve bond issues. Given vast disparities in school districts' property wealth, gross inequities in school facilities will remain without new state or federal funding. With emerg ing research establishing the critical role of the physical environment of schools in student success, adequate and equitable funding of infrastructure takes on new urgency.

Background It is well recognized that the presence of positive surgical margins (PSM) after radical prostatectomy (RP) adversely affects cancer specific outcomes and recent evidence from randomized trials supports the use of adjuvant radiotherapy in these cases. However, not all of the patients with PSM develop disease recurrence and the policy of adjuvant radiation could result in considerable over-treatment. We investigated the ability of early postoperative prostate specific antigen (PSA) and PSA decline rates to stratify the risk of disease progression during the first weeks after the surgery thereby allowing adequate time for planning eventual adjuvant therapy. Methods We studied 116 consecutive patients with the finding of PSM after RP for localized prostate cancer between 2001 and 2012. No patients were treated with radiation or hormonal therapy. An intensive postoperative PSA monitoring using ultrasensitive assay started first at day 14 after the surgery, then at day 30, 60, 90 and 180, and subsequently in 3 monthly intervals. Biochemical recurrence (BCR) presented the failure of surgical treatment and it was defined as PSA ≥0.2 ng/ml. The ability of PSA decline parameters to predict BCR was assessed using Cox regression model and area under the curve (AUC) calculation. Results Overall 55 (47%) patients experienced BCR during median follow-up of 31.4 months (range 6–69). Preoperative PSA, pathologic Gleason sum and pathologic grade failed to reveal any association with observation of BCR. Postoperative PSA levels achieved significant predictive accuracy already on day 30 (AUC 0.74). PSA >0.073 ng/ml at day 30 increased significantly the risk of BCR (HR 4.35, p

Background. Prostate-specific antigen (PSA) is a glycoprotein produced by the prostate gland and its production can be enhanced in benign and malignant diseases. The introduction of PSA testing has greatly increased the detection of prostate cancer. However there is continuing controversy and confusion over the most appropriate application of the PSA test. Methods. PubMed and Web of Science databases were used to search original and review articles on the historical aspects, clinical utilization and possible future directions in PSA. Conclusions. After its discovery, PSA was quickly established as an exquisitely sensitive tumor marker for prostate cancer detection, assessment of treatment responses and follow-up among patients with prostate cancer. Nevertheless, controversy exists about the proper threshold for recommending prostate biopsy. If this limit is lowered to improve the sensitivity even more, patients with low-risk prostate cancer would be subsequently detected. Post-treatment PSA levels can certainly provide valuable information about the effectiveness of the therapy given. Recently introduced ultrasensitive PSA detection techniques are offering new insight into the changes in serum PSA at very low concentrations. This has resulted in identification of valuable postoperative prognostic variables together with the possibility of earlier cancer relapse detection. The development of assays that may show superior sensitivity and specificity in prostate cancer diagnosis is focused on proteins possibly complexed with PSA and other potential markers detectable both in serum and urine. The goal of newly discovered prostate cancer biomarkers is greater cancer specificity in order to reduce the overdiagnosis, overtreatment and financial cost.

We investigated the expression of cell-associated CAIX protein in histological sections of the transitional cell carcinoma (TCC) of the urinary tract and of the soluble form of CAIX (s-CAIX) shed by the tumor into the serum and urine of TCC patients. A total of 23 patients with histologically confirmed TCC or squamous cell carcinoma (SCC) were enrolled in the pilot study. Sixteen healthy individuals served as controls. Membrane-bound CAIX was present in the tumor cells near the endoluminal surface. Necrosis was observed in only 4 samples. Using Western blots, s-CAIX concentrated from urine was visualized as a double band at 50 and 54 kDa. In most cases, the presence of s-CAIX in the urine correlated with CAIX expression in the tumor. On the other hand, s-CAIX did not exceed the normal level in the serum of TCC patients. Urine from patients with TCC of the urinary bladder and renal pelvis contained s-CAIX, allowing the detection of tumors in approximately 70% of the patients. Moreover, two additional patients with suspected, but unconfirmed bladder tumor, with s-CAIX detected in urine, developed tumors identified as TCC within six months. We suggest that after a simple, rapid and sensitive test, monitoring s-CAIX levels in urine will be developed, it may be useful for early detection of relapse in patients following transurethral tumor resection.

A primary assumption in the design of stream restorations is that the sediment supplied to the restoration reach should be transported out of the restoration reach. In watersheds that have been disturbed by human activity, however, the supply gravel and sand that form bedload-material load can be excessive, necessitating that the channel be designed to produce high boundary stresses sufficient to maintain transport. A more practical approach to restoration design would be the gross management of coarse and fine-grained sediments through either removal of the excess sediment sources or storage of the supplied sediment. This sediment management concept was employed in the restoration design for Obion Creek, located in the western Kentucky region of the Coastal Plain. Channelization of most streams in the Obion Creek watershed led to severe channel incision in most tributaries and aggradation of the Obion Creek channel bed at other locations. Upstream channels had incised, mobilizing the loess, sand, and gravel that composed the surrounding hills. The channelized reach eventually filled with sediment and debris, forcing water to flow overland in heavily braided patterns for nearly two miles before entering a recognizably active silt-bed channel. This existing valley plug was incorporated into the restoration design, allowing the channel to accumulate gravel and coarse sand and to splay fine sand and silt on a wide floodplain. To transport silt to the downstream channel, historic channels capable of transporting only silt were connected to the restored channel and reactivated. In the case of Obion Creek, prior modifications of the channel network and changes in hydrology had caused changes in the sediment regime. By incorporating sediment storage into the design, the restoration was able to manage the load while still supplying enough silt to maintain the downstream channel.

The challenges in improving and sustaining success of children from multicultural backgrounds with disabilities in urban school districts manifest themselves in the contextual dynamics of legal, accountability, demographic, and fiscal terrains. Within each of these areas, educational leaders must solve existing problems of underservicing, overidentifying, inadequately funding, and unnecessarily placing multicultural students in restrictive special education placements. In this article, we focus on these terrains.

The environmentally friendly modification of gas turbine combustion chambers is a process for altering the structure of combustion, mainly in the primary zone in order to reduce the emission of NOx , CO, and solids into the atmosphere. The ecological modernization of gas turbines that are currently in operation is a continually topical subject because there are several thousand turbine units in Europe that do not meet current emission limits. At the same time, it can be expected that the emission limits for these turbines operating in the European Union will be reduced to NOx≤75 mg/m3 , CO≤100 mg/m3 in working range of 40–100% of the gas turbine output after the year 2010. The authors have developed a new construction of a hybrid low-emission natural gas burner. Developmental work was performed both on one burner and also in a burner group consisting of seven hybrid burners. Results will be presented in this paper for model conditions for the atmospheric test rig and their re-calculation to the operational parameters on the real gas turbine. A conception with variable primary section combustion chamber geometry has been used to achieve low emissions in a wide range of gas turbine output allowing the organization of the combustion process with a constant gas/air mixing ratio coefficient. A prototype of a combustion chamber with a hybrid burner group with control of the primary air mass flow has been manufactured and tested in a 6 MW gas turbine operating in a gas pipeline compressor plant. The achieved emission characteristics will be presented and compared with precalculations. The experiments made on the real gas turbine have proven the possibility of meeting the target emission limit performance of NOx≤50 mg/m3 , CO≤50 mg/m3 . Other possibilities how to reduce harmful emissions for this burner type will be presented in this paper.Copyright © 2007 by ASME

Currently, more than 1,500 gas turbines are in operation on natural gas transmission lines all over Europe. These turbines do not comply with the requirements for toxic substances content in exhaust gases. Therefore, an environmentally friendly update of these turbines is a hot topic now, especially because these turbines are supposed to remain in operation for another 10 or 15 years. Besides, environmentally friendly update is a specific issue that differs from the development of a new low-emission combustion chamber. The authors participated in environmentally friendly update of more than 500 gas turbines of this design in Russia, Ukraine, Slovakia, Czech Republic, Germany, and Hungary. As new emission limits are expected to be issued in the EU, a new low-emission burner was developed that makes use of a combination of kinetic and diffusion combustion to achieve low NOx and CO emissions. The burner operation in combustion chambers of gas turbines is characterized by a wide range of the coefficient of excess air from idle run to full performance. Therefore, the control of the quantity of primary air is necessary. The paper will describe the main stages of the burner research. Tests were performed on an atmospheric pressure test rig where the basic characteristics were gained. The influence of pressure was examined on a special test rig at 0.75–1.1 MPa of pressure. Tests have confirmed that the required NOx and CO emission limits can be achieved with the designed burner. The low emission burner was used for the combustion chamber of a 6 MW gas turbine. The tests performed on a part of a model burner will be presented and an analysis of measurement results will be given.

Results of the environmental update of GT-750-6 (“Nevsky Zavod”, 6 MW), KWU VR-438 (“Siemens”, 10 MW), MS-3002 (“General Electric”, 10 MW) gas-turbine unit combustors were examined. On the basis of some specific features of design and operating process in the combustors, original engineering approaches of their update using a technique of localized air blow into the fire space extreme temperature zones were developed. The technique was demonstrated to be effective for a variety of combustors. Using the technique, one needs no considerable changes of the combustor design. The fuel system and gas turbine plant automatic control and governing systems remain virtually intact.Copyright © 2000 by ASME

The exhaust of nitrogen oxides into atmosphere is the most stringent environmental challenge in the operation of gas pipeline gas turbine plants. In 1991–1993 NITI EM along with EKOL retrofitted over 170 GTK-10 and GT-750-6 type gas turbine combustors of the “Tyumentransgas” and “Transit” (Czech Republic) gas transmission enterprises. Operations were carried out directly at the gas pumping stations. Emissions of the retrofitted units are within a range of 135–175 mg/Nm3 of oxides of nitrogen (NOx) referred to 15% O2 and carbon monoxide (CO) content of the exhaust gases does not exceed 100 mg/Nm3, at 15% O2.