Nanolayered TiN/CrN multilayer coatings were deposited on silicon substrates using a reactive DC magnetron sputtering process at various modulation wavelengths (
Λ), substrate biases (
V
B) and ...substrate temperatures (
T
S). X-ray diffraction (XRD), nanoindentation and atomic force microscopy (AFM) were used to characterize the coatings. The XRD confirmed the formation of superlattice structure at low modulation wavelengths. The maximum hardness of the TiN/CrN multilayers was 3800
kg/mm
2 at
Λ=80
Å,
V
B=−150
V and
T
S=400°C. Thermal stability of TiN, CrN and TiN/CrN multilayer coatings was studied by heating the coatings in air in the temperature range (
T
A) of 400–800°C. The XRD data revealed that TiN/CrN multilayers retained superlattice structure even up to 700°C and oxides were detected only after
T
A⩾750°C, whereas for single layer TiN and CrN coatings oxides were detected even at 550°C and 600°C, respectively. Nanoindentation measurements showed that TiN/CrN multilayers retained a hardness of 2800
kg/mm
2 upon annealing at 700°C, and this decrease in the hardness was attributed to interdiffusion at the interfaces.
Autocatalytic ternary Ni–Sn–P, Ni–W–P and quaternary Ni–W–Sn–P films were prepared using alkaline citrate-based baths and compared with binary Ni–P coatings. Energy dispersive analysis of X-ray ...(EDAX) showed that binary Ni–P deposit contained 11.3
wt.% of phosphorus. Codeposition of tungsten in Ni–P matrix resulted in ternary Ni–W–P with 5
wt.% P and 7.8
wt.% of tungsten. Incorporation of tin led to ternary Ni–Sn–P deposit containing 0.4
wt.% Sn and 10.3
wt.% P. Presence of both sodium tungstate and sodium stannate in the basic bath had resulted in quaternary coating with 6.9
wt.% W, traces of Sn and 6.4
wt.% P. X-ray diffraction patterns of all the deposits revealed a single, broad peak which showed the nanocrystalline nature of the deposits. For the first time in related literature, the presence of a metastable phase Ni
12P
5 in ternary deposits is reported in the present study. Metallographic cross-sections of all the deposits revealed the banded/lamellar structure. Scanning electron microscopy (SEM) studies of the deposits showed smooth nodules for ternary deposits, but coarse and well-defined nodules for quaternary deposits. DSC studies of phase transformation behavior of the ternary Ni–Sn–P deposit revealed a single sharp exothermic peak at 365
°C. However, ternary Ni–W–P and quaternary Ni–W–Sn–P deposits exhibited a low temperature peak at 300
°C, a split type high temperature peak at 405 and 440
°C and a very high temperature peak at 550
°C. Higher activation energy values were obtained for W-based alloy deposits. Presence of W and Sn has helped to retain high microhardness values even at higher temperatures indicating an improved thermal stability.
Carbon dots are promising scaffolds for multifunctional therapeutic systems because of their fluorescence property, good biocompatibility, and low toxicity. In this work, we prepared nitrogen-doped ...carbon dots through an aqueous phase strategy using folic acid as precursor. The carbon dots possess many attractive features including uniform dispersion with size about 9 nm, bright photoluminescence, high photoluminescence quantum yield of 23%, and low toxicity, making them excellent imaging probes for biomedical applications.
This article presents a comprehensive analysis of fractional order proportional integral (FOPI) and integer order proportional integral (IOPI) controllers for voltage and frequency control of a ...variable speed hybrid standalone wind energy conversion system. Variations in wind velocity and load introduce the changes in terminal voltage and frequency. This can be controlled by an appropriate controller with satisfactory response. In this work, FOPI controller is proposed for controlling the terminal voltage and frequency. Dual second order generalized integral phase locked loop (DSOGI‐PLL) is utilized to track the system frequency. Fractional‐order controller is implemented for voltage source converter, which makes it robust due to their fractional characteristics. FOPI (PIλ) provides an additional degree of freedom (λ), along with proportional gain (Kp) and integral gain (Ki). The robustness of the controller is validated through simulations in MATLAB/simulink and its performance is compared with IOPI under various operating conditions. The results show that, FOPI based controller is able to maintain the terminal voltage and frequency constant with improved transient response in comparison to IOPI. Finally, performance assessment of the controllers is carried out using performance metrics.
According to the latest report of the World Health Organization, 7 lakh 83 thousand people die due to polluted water every year in India. The main challenge of the Government of India is to provide ...clean water to the public. Therefore, in the study presented, an attempt has been made to know why there is pollution of drinking water, what types of diseases are caused by this polluted water, d. An attempt has been made to know its negative effects and pure drinking water treatment. The data and facts have been compiled on a secondary basis.
विष्व स्वास्थ संगठन की ताजा रिपोर्ट के अनुसार भारत में प्रतिवर्ष 7 लाख 83 हजार लोग प्रदूषित जल की वजह से मरते है। जनता को साफ पानी पहुचाना भारत सरकार की मुख्य चुनौति है। अतः प्रस्तुत अध्ययन में यह जानने का प्रयास किया गया है कि पेयजल प्रदुषण क्यों होता है घ् इस प्रदूषित जल से किस प्रकार की बीमारियाँ उत्पन्न होती है घ् इसके नकारात्मक प्रभाव एवं शुध्द पेयजल उपचार को जानने का प्रयास किया गया है। आंकड़ो व तथ्यों का संकलन द्वितीयक आधार पर किया गया है।
Research Summary - Colors have a profound effect on our brain, body and emotions. The imbalance of colors is the cause of disease. If the treatment method of colors removes this imbalance, then a ...person can become healthy and disease free. In the study presented, an attempt has been made to know what is the color therapy system, whether it can lead to disease diagnosis, whether it is a less expensive method, etc. an attempt has been made to know things.
शोध सारांष - रंगों का हमारे मस्तिष्क, शरीर व भावनाओं पर गहरा असर पड़ता हैं। रंगों का असन्तुलन रोग का कारण होता है यदि रंगों की चिकित्सा विधि द्वारा इस असन्तुलन को दूर कर दिया ताय तो व्यक्ति स्वस्थ एवं रोग मुक्त हो सकता हैं। प्रस्तुत अध्ययन में यह जानने का प्रयास किया गया है कि रंग चिकित्सा प्रणाली क्या है घ् क्या इससे रोग निदान हो सकता है घ् क्या यह कम खर्चीली पद्धति है घ् आदि बातों को जानने का प्रयास किया गया है।
Glioblastoma multiforme is an aggressive, invasive brain tumour with a poor survival rate. Available treatments are ineffective and some tumours remain inoperable because of their size or location. ...The tumours are known to invade and migrate along white matter tracts and blood vessels. Here, we exploit this characteristic of glioblastoma multiforme by engineering aligned polycaprolactone (PCL)-based nanofibres for tumour cells to invade and, hence, guide cells away from the primary tumour site to an extracortical location. This extracortial sink is a cyclopamine drug-conjugated, collagen-based hydrogel. When aligned PCL-nanofibre films in a PCL/polyurethane carrier conduit were inserted in the vicinity of an intracortical human U87MG glioblastoma xenograft, a significant number of human glioblastoma cells migrated along the aligned nanofibre films and underwent apoptosis in the extracortical hydrogel. Tumour volume in the brain was significantly lower following insertion of aligned nanofibre implants compared with the application of smooth fibres or no implants.
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