علیرضا خورسندی

. An annular cell with elliptical cross section and small physical size is introduced and simulated for increasing the absorption length in the spectroscopy. In this investigation by changing of the geometrical radius of the ellipse an absorption length of 15.50 m is obtained. By the optimization of the cell and including the sagittal and tangential radius of the ellipse that reflect the beam, it is shown that at the obtained absorption length, it is possible to reduce the divergence of the beam down to 54 µm. Then, signal-to-noise ratio (SNR) is calculated for R(16) CO2 absorption line by assuming that the cell is filled by the gas. The results of this calculation indicated that under optimum condition the SNR can be increased up to 310. Finally, the cell is optimized using Genetic algorithm by including all the effective parameters which affect the efficiency of the cell. We found that in the best case an absorption length of 8.24 m with a SNR of 107 can be achieved when the geometrical radius of the cell being fixed at 5.95 and 4.59 cm.

In this article, we will consider the live burial of girls and the historical reality of this act. According to documents and evidence such as poetry and prose of pre-Islamic period (Jahiliyyah), and holy verses and sayings, it seems that the live burial of girls was a truth of that time and even of our present age. However, the missing bit of information is whether it was limited to Arabs in one time and moment in a specific tribe or it was (is still) practiced by members of other nations and races. The evidence shows that not all Arabian tribes performed this horrid act. Many Arabs held great respect for girls and women given the existence of business women and poets in Jahiliyyah period and the emergence of many outstanding figures in that period such as Al-Khansā in literature and Khadijahin in business. Quran is not just for one period, age, and place, but it addresses all other nations with different races and religions. The live burial of girls is not essentially limited to Arabs or a specific period of time in Quran. Therefore, it has a background in other races and nations. The exaggeration of ascribing this act to only Arabs in Quran has political and promotional aspects, which could be ignored. This horrifying tradition was originated before the birth of Christ and continued to exist in different non-Arab nations and communities Ali, 1970). The ironic meaning and the dictionary meaning of live burial of girls (i.e., the lack of respect for girls and women in different parts of life and not giving them credit for determining their fate and that of other members of society) suggest that the history of Arab and non-Arab nations before and after Islam (even in the present age) includes many cases of disrespect and humiliation of women. Some tribes used to kill widows and bury them close to their diseased husband. Some other buried them
alive in their husband's graves (Maknoon & Sanapoor, n.d.). In the civilized nations prior to Islam, women had the right of ownership but no right of disposal (Tabatabaei, n.d.). Thus, Quran uses the phrase "dont kill" to prevent all men in the past and present ages, including Arabs and non-Arabs, from performing such a despicable act. Given the poetry and prose of pre-Islamic period (Jahiliyyah), and holy verses and sayings on live burial of girls, it could be understood that a few poems have remained that describe or praise this immoral act, which are as follows: The act was not common in all Arab tribes but only in few. Because if it had been popular, it would have been reflected in Arabic poetry. Furthermore if this had been the case, all Arabs would have been proud of it and they would have blamed those who did not kill their daughters.(Abd, 1989). In those tribes where live burial was practiced, there were people who opposed it by different means. It should also be noted that if all members of a tribe had killed their daughters, after some time the number of girls would have dropped and the tribe would have simply died out. (Abdul Satar, 2010 ) Motives for killing of siblings were different in various tribes. The most significant of those reflected in both poetry and prose were hatred, prejudices, perceiving of girls as having bad omen, fear of poverty etc. However, it may be stated that the most important reason for killing of siblings (whether girl or boy) was poverty that made the parents do such an evil act.(Fazlollah, 1984) Quran has severely criticized this action, and Prophet Muhammad (peace be upon Him) has expressed his hatred for this act by his own behaviors and sayings. The position taken by Quran was general, and it addressed all human beings in all times.(Tabatabai, n.d.). Since there are few poems on this issue, it seems that the live burial of siblings was not acceptable for any tribe. It was an individual act done on the basis of different forces and obligations. It was also criticized and admonished by other people. (Al- Ghazali. n.d). Because of the fact that this act was more often practiced by other nations and communities rather than Arabs, it may be stated that Arabs have been heavily disparaged regarding this issue (live burial of girls) mainly because of the disputes between them and other races.

Questions are real if they are about what we do not know. But, sometimes they are used for purposes other than this primary purpose. In such cases, they are referred to as rhetorical questions. Rhetorical questions are one of the controversial issues in rhetoric. Some scholars think that this area belongs to semantics; some think it falls in the same area as figures of speech. This article intends to explores different purposes of rhetorical Questions in the Holy Quran and provide Quranic examples to support the claims. There are two kinds of questions in the Quran: questions posed by God and Questions narrated from others. As God is omniscient and never seeks information, all these questions must be considered as rhetorical questions. Therefore, to better understand the secondary purposes of these questions, we have examined only questions which are posed by God to help the audience follow the right path.

A novel compact fiber-coupled NIR system based on a DFB diode laser source is employed as a portable and sensitive gas sensor for trace detection of combustion pollutant molecules. We demonstrate the performance of such an NIR gas sensor by tracing the absorption lines of CO and CH4 using 2f-WMS technique at moderate temperature of T ~ 600°C in the recuperator channel of an industrial furnace provided by Mobarakeh steel company. This measurement shows the excellent sensitivity of the applied NIR gas sensor to the on-line and in-situ monitoring of such molecular species.

Two continuous-wave (cw) single mode diode-lasers (Toshiba TOLD 9150 and Sharp LT024MDO) are applied as pump and signal sources to obtain difference-frequency generation (DFG) in the mid-infrared (MIR) region by using an AgGaS2 crystal with a length of 30 mm for 90° type I phase-matching. Tuneable MIR laser radiation around 5 µm is obtained with an output power in the order of hundred nW while the diode lasers are operated at 20 and 30 mW around their centre wavelengths 789 and 681 nm, respectively. To demonstrate the applicability of this MIR-DFG laser spectrometer we recorded the absorption spectrum of CO for the P(21) rotational line at 2055.4 cm-1 in a 10 cm long cell and in the flame of a McKenna burner in order to estimate the self-broadening coefficient of CO, the collisional-broadening of CO with CO2, and the CO concentration distribution in the flame.