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The present investigation deals with how minor elements (their oxides: MgO, Na2O and SO3) in industrial kiln feeds affect (i) chemical reactions upon clinkering, (ii) resulting phase composition and microstructure of clinker, (iii) hydration process during cement production. Our results show that all these points are remarkably sensitive to the combination and interference effects between the minor chemical species mentioned above. Upon clinkering, all the industrial raw meals here used exhibit the same formation temperature and amount of liquid phase. Minor elements are preferentially hosted by secondary phases, such as periclase. Conversely, the growth rate of the main clinker phases (alite and belite) is significantly affected by the nature and combination of minor oxides. MgO and Na2O give a very fast C3S formation rate at T > 1450 K, whereas Na2O and SO3 boost C2S. After heating, if SO3 occurs in combination with MgO and/or Na2O, it does not inihibit the C3S crystallisation as expected. Rather, it promotes the stabilisation of M1-C3S, thus indirectly influencing the aluminate content, too. MgO increseases the C3S amount and promotes the stabilisation of M3-C3S, when it is in combination with Na2O. Na2O seems to be mainly hosted by calcium aluminate structure, but it does not induce the stabilisation of the orhtorhombic polymorph, as supposed to occur. Such features play a key role in predicting the physical-mechanical performance of a final cement (i.e. rate of hydration and hardening) when used as a bulding material.

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Idiopathic low back pain can be considered as a chronic condition, characterized by recurrent episodes of pain and functional limitation. The aim of this study is to compare two therapeutic methods to treat this chronic disease: the oxygen-ozone therapy and the diathermy through Tear^® therapy. Two groups of 10 patients each who suffered from postural idiopathic low back pain due to different pathologies have been recruited. All selected patients have been evaluated through spinometry and have been given the <em>Oswestry low back pain disability questionnaire</em> to fill in at the beginning of the treatments and at the end of them with a three-month follow-up. The first group underwent a diathermy treatment through Tecar^® therapy, whilst the second group received an oxygen-ozone therapy treatment through a paravertebral lumbar infiltration; both treatments have been associated with a standard physiokinesitherapy treatment. Data collected through Formetric spinometry show an improvement in both groups, but in the second group (treated with oxygen-ozone therapy+physiokinesitherapy), the improvement is greater (from 6% to 57%) against the first group (from 20% to 38%). In conclusion, the study has cor roborated the validity of both treatments leading to improvement of symptomatology, but while one treatment leads to some relapses after a few months, the second one has a greater healing effect, which preserves over time.

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