In this study, pebble bed as an absorber and storage material was placed in a south facing, flat plate air-type solar collector at fixed tilt angle of (45°). The effect of this material and differ- ent parameters on collector efficiency has been investigated experimentally and
theoretically. Two operation modes were employed to study the performance of the solar air heater. An inte- grated mode of continuous operation of the system during the period of (11:00 am – 3:00 pm) and non-integrated mode in which the system stored the solar energy through the day then used the stored energy during the period of (3:00 pm – 8:00 pm). The results of parametric study in case of continuous operating showed that the maximum average temperature difference of air between inlet and outlet sections observed on (0.018 kg/s) air mass flow rate were exceeded (17°C) and the maximum outlet temperature that got was exceeded (34°C) for the three months (December, January and February) of experiments. Average efficiency was ranged from 53% to 65%. In the case of storage and then operating, the maximum outlet air temperature was ranged from (27°C) up to (31°C) then
decreased with spend of energy to reach (13°C) to (18°C) and the maximum storage energy was (165.14 W) for the porosity of (0.29) , height of (20 cm) and (0.01 kg/s) mass flow rate. The results also, showed that the solar air collector supplied a solar heating fraction (SHF) with an average of (0.65) for a meeting room (3 * 4 * 7 m) located in Baghdad as a case study.
Throughout Agriculture has mostly relied on the use of natural fertilizers throughout human history, which are compounds that increase the nitrogen levels in the soil. Modern agriculture was made possible by the introduction of synthetic fertilizers at the end of the 19th centuryproduction of agriculture. Their application enhanced crop yields and sparked an agricultural revolution unlike anything the world had ever seen.In the near future, synthetic fertilizers are anticipated to continue to have a significant impa ct on human life, both positively and negatively. They are frequently utilized for producing all t ypes of crops and are essential to plant growth. The significance of synthetic fertilizers is their ability to provide the soil w
... Show MoreSystemic lupus erythematosus (SLE) is an autoimmune disease with polymorphic expression. B cells have an essential contribution in immune system activation via the production of different cytokines and functioning as potent antigen-presenting cells. Therefore, a drug that particularly targets B cells may represent an ideal therapeutic approach for SLE. Rituximab (RTX), an anti-CD20 monoclonal antibody causing transient B-cell depletion, has been used to manage SLE. This study aims to assess Rituximab effects on lupus nephritis (LN) patients when added to conventional immunosuppressants. Twenty four patients, 15-32 years old, with class III/IV/V LN were involved in this study. All were on steroids before lupus nephritis occurrence. They were
... Show MoreSystemic lupus erythematosus (SLE) is an autoimmune disease with polymorphic expression. B cells have an essential contribution in immune system activation via the production of different cytokines and functioning as potent antigen-presenting cells. Therefore, a drug that particularly targets B cells may represent an ideal therapeutic approach for SLE. Rituximab (RTX), an anti-CD20 monoclonal antibody causing transient B-cell depletion, has been used to manage SLE. This study aims to assess Rituximab effects on lupus nephritis (LN) patients when added to conventional immunosuppressants. Twenty four patients, 15-32 years old, with class III/IV/V LN were involved in this study. All were on steroids before lupus nephritis occurrence. They were
... Show MoreBecause of its importance in the world, Middle East area is one of the competition areas between the major and great powers. Among those powers are Russia and United states of America. The competition between these two powers to control Syria is greatly clear since 2011. It is also one of the most important subject in the international politics. This importance comes from the importance of Russia and the United States of America besides importance of the Middle East. At the end of the cold war, United States of America maintained its role in the international system and became the only pole that dominated the international affairs while Russia tried to overcome the challenges inherited from the former Soviet Union, and it succeeded in th
... Show MoreBackground: Malignant lymphoma is a term that describes primary tumors of the lymphoreticular system, almost all of which arise from lymphocytes.MMP-1 is the most ubiquitously expressed interstitial collagenase, a subfamily of MMPs that cleaves stromal collagens. It is also called collagenase-1.TIMPs which inhibits MMP activity and thereby restrict extracellular matrix breakdown, TIMP-1 is a stromal factor that has a wide spectrum of functions in different tissues. Material and Methods: This study was performed on (68) formalin-fixed, paraffin-embedded blocks, histopathologically diagnosed as lymphoma (head and neck lesions). Immunohistochemical staining of MMP1and TIMP1 was performed on each case of the study sample. Results: The expressio
... Show MoreThis work involves synthesis of novel Schiff bases derivatives contining isoxazoline or pyrazoline units starting with chalcons . 4-Aminoacetophenone was react with pnitrobenzaldehyde or p-chlorobenzaldehyde in basic medium giving chalcones [I]a,b by claisenschemidt reactions. The chalcones [I]a,b were reacted with hydroxylamine hydrochloride giving isoxazolines [II]a,b in basic medium. The chalcone [I]a could also reacted with hydrazine hydrate to give pyrazolines [III]a . The novel Schiff bases with structural formula [VIII]n , [IX]n , [X]m and [XI]m were prepared by the reaction of amino compounds ; isoxazoline [II]a,b and pyrazolines [III]a with monoaldehydes [VI]n and dialdehydes [VII]m , respectively in dry benze
... Show MoreThis work involves the synthesis and characterization of asymmetrical pyromellitdiimide derivatives [VII]a-f by four sequences steps reaction . One mole of pyromellitic dianhydride was reacted with one mole of various primary aromatic amines [2aminothiazole , 2-aminobenzothiazole , 5-(4-amino phenyl)-1,3,4-oxadiazole-2-thiol , 4-nitro aniline , 4-chloro aniline , 4-toludine] in excess of dry acetone to produce six compounds (Nsubstituted-pyromellitamic monoacid) [IV]a-f . These new compounds [IV]a-f were converted to the corresponding N- substituted- pyromellitmonoimide [V]a-f when heating then at (8090) 0C in sodium acetate-acetic anhydride system .The compounds [V]d-f were allowed to react with one m
... Show MoreAcquisition provisions in Islamic jurisprudence
This work was conducted to determine the volumetric mass transfer coefficient (Ky.a) infixed bed adsorption using hexane-benzene mixture by adsorption onto a fixed bed of white silica gel. Benzene concentration was measured by gas chromatography. The effect of feed flow rate and initial concentration of benzene in hexane-benzene mixture on the volumetric mass transfer coefficient and on the adsorption capacity of silica gel was investigated.
In general, the volumetric mass transfer coefficient increases with increasing hexane flow rate, and with increasing initial concentration of benzene in the mixture. The ultimate value of (Ky.a) was at 53 ml/min of hexane flow rate with benzene initial concentration of (6.53 wt. %), and it wa
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