A new green index as an overall quantitative green performance indicator of a facility

Green assessment tools such as the Building Research Establishment Environmental Assessment Method, Leadership in Energy and Environmental Design, Comprehensive Assessment System for Building Environmental Efficiency, GREEN STAR and HK-BEAM have been used worldwide. These tools, which utilise qualitative, credit-based rating system have several limitations. Firstly, they can only provide a relative measure of the greenness of a facility. Secondly, there is the possibility that the ratings assigned may differ from one user to another depending on the needs and priorities of an organisation, a country, or a region. Several studies have also highlighted that such credit-based systems involve piece-meal (Zuo and Zhou in Renew Sustain Energy Rev 30:271–281, 2014), as opposed to integrated evaluation of the green criteria, and the greenness of a facility. This paper proposes a new Green Index (GI) as a tool for assessing the level of greenness of a facility that overcomes the aforementioned limitations. The use of stock market composite index as a basis for the GI development has enabled an established tool for assessing stock market performances to progress into the domain of industrial and commercial facility management. Development of the GI involves two steps, namely the development of a weighting scheme using the factor analysis approach, followed by the composite GI formulation that is based on the stock market composite index. The developed Green Index is based on quantitative analysis and measurement of parameters, and hence, reflect the actual measure of the overall impact of a facility on the environment. With only a single indicator to represent multiple green elements, it makes it easier for facility managers to effectively and quantitatively monitor, analyse, compare and benchmark the actual level of greenness of facilities in new systems designs or a retrofit or conservation programme.     

316L奥氏体不锈钢点蚀的原位声发射监测

为了研究316L不锈钢自然点蚀的生长规律,发展基于声发射技术的小孔腐蚀监测方法,利用声发射技术原位研究了316L奥氏体不锈钢在pH=1.0和中性(pH=6.7)的3.5%NaCl溶液中的自然点蚀状况,同时监测了开路电位E_(OCP);通过扫描电镜对试验后样品的表面形貌进行表征,并通过Matlab平台对声发射信号进行聚类分析。结果表明:316L奥氏体不锈钢的自然点蚀具有不同的孕育周期,声发射信号的获取跟E_(OCP)的变化具有较好的对应关系。在点蚀快速发展阶段,声发射信号具有较高的绝对能量。在Matlab平台上建立了一套信号处理程序,并对声发射信号进行重新定义,对处理后的信号进行声发射信号参数分析,得到了3类较好的声发射信号聚类,来源于不同腐蚀现象或阶段。其中,在点蚀的快速发展阶段主要以高持续时间高计数和高持续时间低计数2类谐振信号为主。     

Sterilizing photocurable materials by irradiation: preserving UV-curing properties of photopolymers following E-beam,gamma, or X-ray exposure

We have developed novel photopolymer gels to function as separators in blood collection tubes. By incorporating antioxidants such as α-tocopherol and nitroxides (TEMPO and TEMPOL), the new formulation can be sterilized with electron beam or gamma rays at a dose level of 17?kGy, without inducing premature curing of the photopolymers. For the blood separator gels that contain α-tocopherol, our results show that α-tocopherol plays a decisive role in impeding C-centered free radical propagation reactions through an H^?transfer mechanism. This mechanism involves the transfer of an H-atom from the hydroxyl group (OH) of α-tocopherol to the propagating C-centered radical leading to the termination of the polymerization. The sterilization radiation-induced premature curing of the photopolymer was also prevented in the blood separator gel containing nitroxides. For the gels containing TEMPO or TEMPOL, inhibition of the premature curing was achieved through an addition reaction or an H-transfer reaction, respectively. Our results also show that while α-tocopherol is not a contributing factor in the subsequent (time-of-use) UV curing of the gels, nitroxides enhance the UV curing process through nitroxide-mediated living free radical polymerization reactions leading to a decrease in UV curing time. The photopolymer separator gels are shown to function advantageously in clinical laboratory testing, especially for cell-free DNA measurements in blood.     

Influence of mode mixity and loading conditions on the fatigue crack growth behaviour of an epoxy adhesive

Adhesive joints usually experience mixed mode and mostly cyclic stresses conditions during their service life. The aim of the current research is to investigate the fatigue behaviour of a structural epoxy adhesive. Pure modes I and II and mixed mode tests were carried out to study the fracture and fatigue crack growth (FCG) behaviour of the adhesive. Compliance‐based beam method was considered for experimental fracture energy measurement. The effects of load level and load ratio on the mode I FCG behaviour and Paris law parameters were also investigated. Result showed that the effect of load level on fatigue crack propagation is more pronounced for lower R ratios. It was found that when the crack faces are closer during the unloading process, the difference between the R² and G_min/G_max is higher. Some possibilities are the crack closure phenomenon, difficulty in measuring the G_min , and the employed data reduction approach.     

Acoustic Emission-Based Methodology to Evaluate Delamination Crack Growth Under Quasi-static and Fatigue Loading Conditions

The aim of this study was to investigate the applicability of acoustic emission (AE) technique to evaluate delamination crack in glass/epoxy composite laminates under quasi-static and fatigue loading. To this aim, double cantilever beam specimens were subjected to mode I quasi-static and fatigue loading conditions and the generated AE signals were recorded during the tests. By analyzing the mechanical and AE results, an analytical correlation between the AE energy with the released strain energy and the crack growth was established. It was found that there is a 3rd degree polynomial correlation between the crack growth and the cumulative AE energy. Using this correlation the delamination crack growth was predicted under both the static and fatigue loading conditions. The predicted crack growth values was were in a good agreement with the visually recorded data during the tests. The results indicated that the proposed AE-based method has good applicability to evaluate the delamination crack growth under quasi-static and fatigue loading conditions, especially when the crack is embedded within the structure and could not be seen visually.     

Formation of dot arrays with a pitch of 20 nm × 20 nm for patterned media using 30 keV EB drawing on thin calixarene resist

We studied the possibility of achieving very fine-pitch dot arrays with a pitch of 20?nm × 20?nm using 30?keV electron beam (EB) drawing on negative calixarene resist. In order to form such patterns, we studied the dependence on resist thickness of the dot size and the packing. We propose EB drawing on an extremely thin film for very highly packed dot-array formation. Our experimental results demonstrate the possibility of forming highly packed dot-array patterns with a pitch of 20?nm × 20?nm and a resist thickness of about 13?nm, which corresponds to about 1.6?Tbits?in(-2).     

Fast-disintegrating sublingual epinephrine tablets: effect of tablet dimensions on tablet characteristics

The purpose of this study was to evaluate the effect of changing dimensions on the hardness (H), disintegration time (DT), and wetting time (WT) of fast-disintegrating epinephrine tablets for sublingual administration as potential first aid treatment for anaphylaxis. Tablet formulations I and II, containing 0% and 10% epinephrine bitartrate, respectively, and weighing 150 mg were prepared by direct compression. Formulations were compressed at a range of forces using an 8/32' die with concave punches (CP); a 10/32' and an 11/32' die with CP and flat punches (FP). Tablet weight variation, content uniformity, thickness, H, DT, and WT were measured. The 8/32', 10/32', and 11/32' dies resulted in tablet thickness of ranges 0.25-0.19', 0.17-0.1', and 0.16-0.08', respectively. The DT and WT using the 8/32' die were相似文献   

Stress ratio effect on fatigue life of tropically weathered rock

This paper investigates the fatigue life of weathered granite and weathered sandstone using a stress ratio of R = 0.17. A small stress ratio is adopted to control data discrepancy between weathered rocks for which stress amplitude is known to affect the fatigue life. The range of varying static strength between weathered rocks, especially for highly weathered rock (grade IV) which has lower static strength, resulted in adopting this small stress ratio. The details of rocks tested, including microscopic petrographic characterization as well as their physical properties obtained from laboratory work, is also explained in this paper. Weathered rock specimens from slightly weathered to highly weathered (grade II, grade III and grade IV) granite and sandstone were used during the investigation. The specimens were representative of rock collected in Sungai Buloh (granite) and Puncak Perdana (sandstone) in Selangor, Malaysia. In order to eliminate the influence of frequency and waveform, all rock specimens (54 in total) were tested under a cyclic compression load with a frequency of 1 Hz using a constant sinusoidal waveform. Result shows that grade IV specimens are the least affected by the small cyclic stress ratio as compared to grade II and grade III specimens. The number of cycles to failure is not dependent on rock weathering grade; it is greatly related to the petrological and microstructure of the individual rock. However, the weathering degree of a rock does contribute to the weakening of the rock's structure, consequently affecting the life of the rock.     

Evaluation of adhesion strength,flammability, and degradation of HBCD‐containing polyurethane adhesives

In this work, moisture curable flame retardant HTPB‐based polyurethane adhesives were synthesized. The influence of HBCD (Hexabromocyclododecane) as flame retardant on adhesion, degradation and change in flammability of synthesized HTPB‐based polyurethane has been studied. Relationship between phase separation in hard and soft domains and adhesion has also been investigated. FTIR analysis was used to determine phase separation in synthesized adhesives. Lap shear test was used to determine adhesion properties of adhesives applied on aluminum and glass substrates. Thermal Gravimetry analysis and Limited Oxygen Index (LOI) tests were carried out on flame retardant adhesives to evaluate effect of HBCD on degradation and flammability. Addition of HBCD to adhesives leads to reduction of thermal stability and lap shear strength for all substrates, in spite of flame retardant adhesives show higher LOI value. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

A hybrid LQR-PID control design for seismic control of buildings equipped with ATMD

This paper presents an efficient hybrid control approach through combining the idea of proportional-integral-derivative (PID) controller and linear quadratic regulator (LQR) control algorithm. The proposed LQR-PID controller, while having the advantage of the classical PID controller, is easy to implement in seismic-excited structures. Using an optimization procedure based on a cuckoo search (CS) algorithm, the LQR-PID controller is designed for a seismic- excited structure equipped with an active tuned mass damper (ATMD). Considering four earthquakes, the performance of the proposed LQR-PID controller is evaluated. Then, the results are compared with those given by a LQR controller. The simulation results indicate that the LQR-PID performs better than the LQR controller in reduction of seismic responses of the structure in the terms of displacement and acceleration of stories of the structure.